<chapter id="using-kmail">

<chapterinfo>
<authorgroup>
<author>
<firstname>Daniel</firstname>
<surname>Naber</surname>
<affiliation><address>
<email>daniel.naber@t-online.de</email>
</address></affiliation>
</author>
<author>
<firstname>David</firstname>
<surname>Rugge</surname>
<affiliation><address>
<email>davidrugge@mediaone.net</email>
</address></affiliation>
</author>
<!-- TRANS:ROLES_OF_TRANSLATORS -->
</authorgroup>
<date>2002-10-03</date>
<releaseinfo>1.5</releaseinfo>
</chapterinfo>

<title>Using &kmail;</title>

<sect1 id="the-mail-reader-window">
<title>The Main Window</title>

<para>The main window is the window that appears
when &kmail; is started. It is divided into three panes:</para>

<variablelist>
<varlistentry>
<term>Folders pane (left pane)</term>
<listitem>
<para>This pane contains the list of your message folders (other email programs
may call them mailboxes). To select a folder, simply click on
it. The messages contained in the folder will now appear in the Headers
pane. The folder list can be displayed in both a short view, which takes up only
a small portion of the left side of the screen, and a long view, which takes up the 
entire left side of the screen but is able to show more mailboxes. You can toggle
between these two views under <guilabel>Appearance</guilabel>/<guilabel>Layout</guilabel>
in the <menuchoice><guimenu>Settings</guimenu><guimenuitem>Configure
&kmail;...</guimenuitem></menuchoice> dialog. Also see the <link
linkend="folders">Folders Section</link> for more information about how to use
folders.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Headers pane (upper right pane)</term>
<listitem>
<para>This pane lists header information (message Status Flags, Sender, Subject,
Date, optionally Size) for the messages in the currently selected folder. Clicking on a header
will select that message and display it in the Message pane. You can also select
more than one message by holding down the &Ctrl; key when clicking on messages.
You may sort the messages by clicking on the column that you wish to
sort. If you click on the same column more than once, sort order will toggle
between ascending/descending.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Message pane (lower right pane)</term>
<listitem>
<para>This pane displays the currently selected message. Attachments appear
at the bottom of the message, either as icons or embedded in the message,
depending on <menuchoice><guimenu>View</guimenu>
<guimenuitem>Attachments</guimenuitem></menuchoice>.
You can scroll through the message page by page
using the <keycap>Page Up</keycap> and <keycap>Page down</keycap> keys, or line
by line using the <keycap>up arrow</keycap> and <keycap>down arrow</keycap>
keys. You can also use <link linkend="keyboard-shortcuts">key shortcuts</link> to skip through 
your messages without having to use the mouse.</para>
</listitem>
</varlistentry>
</variablelist>

</sect1>

<sect1 id="keyboard-shortcuts">
<title>Keyboard Shortcuts</title>

<para>The following keyboard shortcuts are supported in the main window:</para>

<informaltable>
<tgroup cols="2">
<thead>
<row>
<entry>Keyboard Shortcut</entry>
<entry>Action</entry>
</row>
</thead>
<tbody>
<row>
<entry><keycap>Space</keycap></entry>
<entry>Scroll down in the current message or go to the next unread message if you are already 
at the bottom.</entry>
</row>
<row>
<entry><keycap>Right Arrow</keycap> or <keycap>N</keycap></entry>
<entry>Go to the next message in the current folder.</entry>
</row>
<row>
<entry><keycap>Left Arrow</keycap> key or <keycap>P</keycap></entry>
<entry>Go to the previous message in the current folder.</entry>
</row>
<row>
<entry><keycap>+</keycap></entry>
<entry>Go to the next unread message in the current folder.</entry>
</row>
<row>
<entry><keycap>-</keycap></entry>
<entry>Go to the previous unread message in the current folder.</entry>
</row>
<row>
<entry><keycombo action="simul">&Ctrl;<keycap>+</keycap></keycombo></entry>
<entry>Go to the next folder with unread messages.</entry>
</row>
<row>
<entry><keycombo action="simul">&Ctrl;<keycap>-</keycap></keycombo></entry>
<entry>Go to the previous folder with unread messages.</entry>
</row>
<row>
<entry><keycombo action="simul">&Ctrl;<keycap>Left Arrow</keycap></keycombo></entry>
<entry>Walk upwards in the list of folders. Use 
<keycombo action="simul">&Ctrl;<keycap>Space</keycap></keycombo> to actually
enter the folder.</entry>
</row>
<row>
<entry><keycombo action="simul">&Ctrl;<keycap>Right Arrow</keycap></keycombo></entry>
<entry>Walk downwards in the list of folders. Use 
<keycombo action="simul">&Ctrl;<keycap>Space</keycap></keycombo> to actually
enter the folder.</entry>
</row>
<row>
<entry><keycombo action="simul">&Ctrl;<keycap>Space</keycap></keycombo></entry>
<entry>Enter the folder that has focus, &ie; the folder that you navigated
to using <keycombo action="simul">&Ctrl;<keycap>Left Arrow</keycap></keycombo> or
<keycombo action="simul">&Ctrl;<keycap>Right Arrow</keycap></keycombo>.</entry>
</row>
<row>
<entry><keycombo action="simul">&Shift;<keycap>Left Arrow</keycap></keycombo> and
<keycombo action="simul">&Shift;<keycap>Right Arrow</keycap></keycombo></entry>
<entry>Select messages in the header pane, starting with the current message.</entry>
</row>
</tbody>
</tgroup>
</informaltable>

</sect1>

<sect1 id="the-composer-window">
<title>The Composer Window</title>

<para>The composer window is used to write new messages.
It can be invoked via <menuchoice><guimenu>Message</guimenu>
<guimenuitem>New Message...</guimenuitem></menuchoice>
menu or from the <guiicon>New Message</guiicon> icon on the main
window.</para>

<sect2 id="composing-a-message">
<title>Composing a Message</title>

<para>To write your message, fill in the appropriate fields in the
composer window. Use the <guimenu>View</guimenu> menu
to select which header fields are displayed. The <guimenuitem>Identity</guimenuitem>
field offers a <guibutton>Sticky</guibutton> option. If it is checked,
the current identity will become the default identity when you open
a new composer next time.</para>

<para>There are a variety of shortcuts to help
you with writing your messages. The <guibutton>...</guibutton> buttons next to
the <guilabel>To:</guilabel>, <guilabel>CC:</guilabel>, and
<guilabel>BCC:</guilabel> fields will call up the address book so that you can
select addresses from there.</para>

<para>When you start typing an address in the
<guilabel>To:</guilabel>/<guilabel>CC:</guilabel>/<guilabel>BCC:</guilabel>
fields, a popup will appear that offers matching addresses that have been used recently 
and matching addresses from your address book. If you do not like the automatic 
popup you can disable it by clicking with the &RMB; on the field and choosing 
a different completion mode.</para>

<para>Whenever you want to add more than one
recipient in one of the fields, use a comma to separate each address
from the next one. 
<!-- fixme: there's now a setting for this: -->
You may need to specify fully qualified addresses
(&ie; <userinput>user@domain.com</userinput>) even for local
users, depending on your system configuration.</para>

<para>When you are finished with your
message, click the <guiicon>Send</guiicon> icon (the envelope) to send
the message now, or click the <guiicon>Queue</guiicon> icon to put
the message in the outbox. If your message is not finished yet, select
<menuchoice><guimenu>Message</guimenu><guimenuitem>Save in Drafts
Folder</guimenuitem></menuchoice>. If you want to send an <link
linkend="pgp-encrypt-your-messages">encrypted</link>
or <link linkend="pgp-sign-your-messages">digitally signed</link> message, select the
<guiicon>Sign Message</guiicon> resp. <guiicon>Encrypt 
Message</guiicon> icons in the toolbar.</para>

<para>If you have installed and activated at least one of
the <link linkend="configure-security-plugins">encryption plugins</link>
then you can select whether you want to use the
built-in OpenPGP support or the plugin for encryption and/or signing.
Use the built-in OpenPGP support if you want to send clearsigned
messages or inline encrypted messages. If you want to send signed or
encrypted messages with attachments you should use one of the crypto
plugins. Please note that the built-in OpenPGP will <emphasis>not</emphasis>
sign or encrypt attachments.</para> 

</sect2>

<sect2 id="attachments">
<title>Adding Attachments</title>

<para>You can attach files to your message by using one of the methods
below:</para>

<itemizedlist>
<listitem>
<para>Click the <guiicon>Attach File</guiicon> (paper clip) icon and select the file you wish
to attach.</para>
</listitem>
<listitem>
<para>Drag a file from the desktop or another directory into the
composer window.</para> 
</listitem>
<listitem>
<para>Select one of the options in the
<menuchoice><guimenu>Attach</guimenu></menuchoice> menu.</para>
</listitem>
</itemizedlist>

<para>Once a file is attached to your message, it appears in the attachments
pane at the bottom of the composer window. You can use the
&RMB; on each attachment to <guimenuitem>View</guimenuitem>,
<guimenuitem>Save</guimenuitem> or <guimenuitem>Remove</guimenuitem>
the attachment.</para>

<para>Use the <guimenuitem>Properties...</guimenuitem> item to
open the <guilabel>Message Part Properties</guilabel> dialog.
The first field contains the attachment's &MIME;-type. Just like the <guilabel>Name</guilabel>
field, it should be automatically filled with an appropriate value. Sometimes the
&MIME;-type value may be wrong. You can then type in any &MIME;-type or
choose from the list of common &MIME;-types. You can also select an encoding
method for your file from the list of encoding options (normally, the default
value works fine). Check the <guilabel>Suggest automatic display</guilabel> option 
if you want to suggest to the recipient the automatic (inline) display of this part 
in the message preview, instead of the default icon view.</para>
<!-- fixme: depends on the receiver's client -->

<para><application>PGP</application>/<application>GnuPG</application> keys may also 
be attached to your message by using the appropriate options in the
<menuchoice><guimenu>Attach</guimenu></menuchoice> menu. <application>PGP</application>
key attachments are handled like file attachments.</para>

<!-- copied from below -->
<warning><para>Attachments will not be encrypted if you are using 
the built-in OpenPGP support. To encrypt attachments, you have to install
and configure <link linkend="configure-security-plugins">encryption plugins</link>.
</para></warning>
<!-- / copied from below -->

</sect2>

<sect2 id="checking-the-spelling-of-your-message">
<title>Checking the Spelling of your Message</title>

<para>To check the spelling of your message, select
<menuchoice><guimenu>Tools</guimenu>
<guimenuitem>Spelling...</guimenuitem></menuchoice>. &kmail; uses 
<ulink url="/kspell/">&kspell;</ulink> to
check spelling, which is the &kde; frontend to the 
<application>ispell</application> or <application>aspell</application> spelling
checker. Note that you may first need to configure the spellchecker using
<menuchoice><guimenu>Settings</guimenu>
<guimenuitem>Spellchecker...</guimenuitem></menuchoice>.</para>

</sect2>

</sect1>

<sect1 id="folders">
<title>Message Folders</title>

<para>Message Folders are used to organize your email messages. By default, all
message folders are stored in the directory <filename
class="directory">Mail</filename>, which is created in your home directory. When
you first start &kmail; the <guilabel>inbox</guilabel>,
<guilabel>outbox</guilabel>, <guilabel>sent-mail</guilabel>,
<guilabel>trash</guilabel> and <guilabel>drafts</guilabel> folders are created.
These folders each have special functions:</para>

<variablelist>
<varlistentry>
<term><guilabel>inbox:</guilabel></term>
<listitem>
<para>Where &kmail; by default puts your new messages when you ask it to check your
mail. </para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>outbox:</guilabel></term>
<listitem>
<para>Where messages are put while they are waiting to be delivered. Note that
you should not drag and drop messages here to send them, use the <guiicon>Send</guiicon>
icon in the composer window instead.<!-- fixme 3.2: has this been 'fixed'? --></para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>sent-mail:</guilabel></term>
<listitem>
<para>Contains copies of all messages that you have sent.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>trash:</guilabel></term>
<listitem>
<para>Contains all messages that you have moved to trash.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>drafts:</guilabel></term>
<listitem>
<para>Contains messages you started to edit but then saved to this
folder instead of sending them.</para>
</listitem>
</varlistentry>
</variablelist>

<para>You may find that the standard folders are fine for your
needs. Eventually, though, you will probably need folders to help you organize
your messages. To create a new folder, select
<menuchoice><guimenu>Folder</guimenu><guimenuitem>New Folder...</guimenuitem></menuchoice>
The <link linkend="folders-properties-window">folder properties</link> dialog
will then prompt you for the necessary information. If you ever need to change
the settings for a folder, select the folder you wish to modify in the Folders pane and select
<menuchoice><guimenu>Folder</guimenu><guimenuitem>Properties...</guimenuitem>
</menuchoice>.</para>

<para>To move messages from one folder into another, select the message(s) you
want to move and press the <keycap>M</keycap> key or select
<menuchoice><guimenu>Message</guimenu><guimenuitem>Move
To</guimenuitem></menuchoice>. A list of folders will appear.  Select the folder
from the list that you want to move the messages to.  Messages can also be moved
by dragging them from the Headers pane into the Folders pane.</para>

<para>If you want to clear all of the messages out of a folder choose
<menuchoice><guimenu>Folder</guimenu><guimenuitem>Move All Message to
Trash</guimenuitem></menuchoice>. You can use 
<menuchoice><guimenu>Folder</guimenu><guimenuitem>Delete Folder</guimenuitem></menuchoice>
to remove a folder and all its messages and sub folders.</para>

<sect2 id="folders-properties-window">
<title>Folder Properties</title>

<para>The folder's <guilabel>Properties</guilabel> dialog lets you rename and move
a folder and specify all of its properties. Note that most properties
are only available for your own folders and not for default folder like
<guilabel>inbox</guilabel> &etc;. Default folders also cannot be moved
or renamed.</para>

<para>You can make a folder a sub folder if you choose a parent
folder using the <guilabel>Belongs to</guilabel> selection. </para>

<para>The <guilabel>Folder Icons</guilabel> section lets you choose
icons that are different from the default ones in the folder list.</para>

<para>See the <link linkend="folders-format">Folder Format</link> section
for information about the <guilabel>Mailbox format.</guilabel></para>

<para>If you're going to use the folder for a mailing list you may want to add
the mailing list address in the <guilabel>Associated Mailing List</guilabel> section.
You will then be able to use
the <menuchoice><guimenu>Message</guimenu><guimenuitem>Reply
to Mailing-List...</guimenuitem></menuchoice> menu item. It will open a reply with the
mailing list address in the <guilabel>To:</guilabel> field (&ie; it will ignore
the <token>Reply-To</token> of the message). You can also click the
<mousebutton>middle</mousebutton> mousebutton in the Folders pane to post to a
mailing list that is associated with that folder.</para>

<para>The <guilabel>Old Message Expiry</guilabel> section lets you automatically
delete old messages when you exit &kmail; (depending on your settings
in &kmail;'s <guilabel>Folders</guilabel> configuration page) or
via <menuchoice><guimenu>File</guimenu><guisubmenu>Expire
All Folders</guisubmenu></menuchoice>.
<warning><para>Messages that are expired are deleted. They are <emphasis>not</emphasis> moved
to trash, so be careful with this setting.</para></warning>
</para>

<para>With the <guilabel>Identity</guilabel> section you can set your default
identity for new messages. Replies to messages that where sent directly
to you will still default to the message's <quote>To</quote> address if an
according identity is found.</para>

<para>With <guilabel>Show Sender/Receiver</guilabel> you can set the 
visible columns in the header pane. This is useful if you use a
folder to save your own sent messages.</para>

</sect2>

<sect2 id="folders-format">
<title>Folder Format</title>

<para>A message folder can be either in <guilabel>mbox</guilabel> or in <guilabel>maildir</guilabel>
format. <guilabel>mbox</guilabel> saves all messages of a folder to one file,
whereas <guilabel>maildir</guilabel> saves each message to its own file.
<guilabel>maildir</guilabel>, which is the default format, can be considered more
robust, but it can be slower on some file systems. If you are unsure, you should
choose <guilabel>maildir</guilabel>.</para>

<para>Note that there is currently no feature in &kmail; that allows to convert
between both formats automatically - but you can just move all messages from an old
<guilabel>mbox</guilabel> folder to a new <guilabel>maildir</guilabel> folder or
vice versa.</para>

</sect2>

</sect1>

<sect1 id="filters">
<title>Message Filters</title>
<anchor id="filters-id"/>

<para>After using &kmail; for a while, you may find that you have trouble
sorting out the new messages in your inbox when they arrive. Filters allow you
to automatically perform certain actions on incoming messages and to manually
perform actions on selected messages in a folder.</para>

<para>Please note that the filters described in this section are
applied <emphasis>after</emphasis> the messages have been downloaded
from your account. If you want to filter messages on the server, see
<link linkend="popfilters">Download Filters</link>.</para>

<para>Filters consist of a search pattern, whose rules are used as
criteria to determine whether this filter should be applied to a given
message, and a list of filter actions, which describe what is being
done with or to the message if the search pattern matches. Read more
about search patterns and filter actions in the following
subsections.</para>

<note><para> Filters are considered one after the other,
starting with the first filter in the list. The first one whose
pattern matches the given message gets executed. You can request that
the remaining filters also be applied, but the default is to stop
processing at the first matching filter. </para></note>

<para>Usually, filters are used on incoming messages, but they can
also be applied to sent messages or to an arbitrary message or group
of messages. To selectively filter messages, select the messages you
want to filter in the message list and type <keycombo
action="simul">&Ctrl;<keycap>J</keycap> </keycombo> or select
<menuchoice><guimenu>Message</guimenu> <guimenuitem>Apply
Filters</guimenuitem></menuchoice>. This will apply all filters that
have been marked for manual filtering in the <link
linkend="filter-dialog">filter dialog</link> to those messages.</para>

<sect2 id="filter-quick">
<title>Fast Filter Creation</title>

<para>There are two methods for creating a filter: The quick method is
to use <menuchoice><guimenu>Tools</guimenu><guimenuitem>Create
Filter...</guimenuitem></menuchoice>. This will call the filter dialog
and present you with a new filter which has the first rule of the
search pattern and the first action (as <guilabel>move to folder</guilabel>) preset. In
most cases, all you have to do is select the folder where the message
should be moved to. But you can, of course, edit the filter as you
like.</para>

<para>The interesting thing about this method is that creating a
filter on mailing lists will try really hard to find a criterion that
uniquely identifies messages from that list. If it succeeds, the guessed
name of the list is presented in the
<menuchoice><guimenu>Tools</guimenu><guisubmenu>Create
Filter</guisubmenu><guimenuitem>Filter on
Mailing-List...</guimenuitem></menuchoice> menu entry.</para>

<para>The second method is to manually construct a filter from scratch
by calling the filter dialog through
<menuchoice><guimenu>Settings</guimenu><guimenuitem>Configure 
Filters...</guimenuitem></menuchoice>. The filter dialog is described in
detail in the following subsection.</para>
</sect2>

<sect2 id="filter-dialog">
<title>The Filter Dialog</title>
<anchor id="filter-dialog-id"/>

<para>This dialog allows you to manage and edit your list of
filters.</para>

<para>You reach it either via
<menuchoice><guimenu>Tools</guimenu><guisubmenu>Create
Filter...</guisubmenu></menuchoice> or
<menuchoice><guimenu>Settings</guimenu><guimenuitem>Configure 
Filters...</guimenuitem></menuchoice>.</para>

<para>The dialog is divided into four main sections:</para>
<variablelist>
<varlistentry>
<term><guilabel>Available Filters</guilabel></term>
<listitem><para>This group contains the list of filters and some action
buttons to modify the filters, namely to create new filters, to move
them up or down the list, or to delete or rename them. If you select
a filter from the list, its properties are shown in the right-hand half
of the dialog.</para></listitem>
</varlistentry>
<varlistentry>
<term><guilabel>Filter Criteria</guilabel></term> <listitem><para>In
this group you can edit the pattern that messages must match for the
filter to be applied to them. You can select here whether all of the
defined rules must match or whether it suffices that any one of them
matches. See <link linkend="filter-criteria">Search Patterns</link>
below for a detailed description of each search rule type.</para>

<para> You can click on <guibutton>More</guibutton> to get an
additional (initially empty) rule if you want to define more complex
patterns and on <guibutton>Fewer</guibutton> to remove the last
rule. <guibutton>Clear</guibutton> clears the pattern, &ie; it removes
all but two rules from screen and resets those two.</para>
<para>Invalid or empty rules are not evaluated.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>Filter Actions</guilabel></term> <listitem><para>In
this group you can edit the list of actions that is applied to all
messages that match the defined search pattern. See <link
linkend="filter-action">Filter Actions</link> below for a detailed
description of each action type.</para>

<para> You can click on <guibutton>More</guibutton> to get a new,
empty action if you want to define more than one action and on
<guibutton>Fewer</guibutton> to remove the last
action. <guibutton>Clear</guibutton> clears the list, &ie; it
removes all but one action and resets that one.</para>
<para>Invalid or empty actions are not executed.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>Advanced Options</guilabel></term>
<listitem><para> In
this group you can define a few advanced options for filters that
allow you to refine your filtering.</para>
<para>Using the first row
of check boxes, you can toggle the applicability of the corresponding
filter: The <guilabel>to incoming messages</guilabel> check shows whether
it may be considered for incoming messages (&ie; on <guiicon>Check
Mail</guiicon>). The <guilabel>to sent messages</guilabel> check
shows the same for sent messages (&ie; <emphasis>after</emphasis>
<guiicon>Send</guiicon>) and the <guilabel>on manual
filtering</guilabel> check controls whether to apply this filter when
filtering manually (&ie; via <menuchoice><guimenu>Message</guimenu>
<guimenuitem>Apply Filters</guimenuitem></menuchoice>).</para>
</listitem>
</varlistentry>
</variablelist>

<note><para>Filters are automatically named unless you explicitly
rename them using the <guibutton>Rename...</guibutton> button.
The dialog assumes that it should continue auto-naming the filter
as long as the filter name starts with <quote>&lt;</quote>.
</para></note>

<note>
<para>If you apply filter changes, via
<guibutton>OK</guibutton> or <guibutton>Apply</guibutton>, only valid
filters are actually copied to the internal filter manager.</para>

<para>A filter is considered invalid if</para>

<orderedlist>
<listitem><para>the search pattern contains only empty rules or</para></listitem>
<listitem><para>the action list is empty.</para></listitem>
</orderedlist>

<para>Similarly, empty rules and actions are removed from the pattern
and action list respectively, before the filter is saved.</para>
</note>

</sect2>

<sect2 id="filter-criteria">
<title>Search Patterns</title>

<para>The most common use of filters is to filter on the sender of
messages. This can be done by choosing <guilabel>From</guilabel>. A
good bet for a mailing list would be
<guilabel>&lt;recipients&gt;</guilabel>. But there are other criteria
a filter can search for. Note that all patterns are interpreted 
case-insensitively:</para>

<variablelist>
<varlistentry>
<term><guilabel>&lt;message&gt;</guilabel></term>
<listitem>
<para>Searches the whole message (&ie; headers, body and attachments,
if any).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>&lt;body&gt;</guilabel></term>
<listitem>
<para>Searches the body of the message.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>&lt;any header&gt;</guilabel></term>
<listitem>
<para>Searches the headers of the message.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>&lt;recipients&gt;</guilabel></term>
<listitem>
<para>Searches the <quote>To</quote> and <quote>CC</quote> header fields of the message.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>&lt;size&gt;</guilabel></term>
<listitem>
<para>Sets upper or lower bounds on the message size.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>&lt;age in days&gt;</guilabel></term>
<listitem>
<para>Sets upper or lower bounds on the message age.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Any other name</term>
<listitem>
<para>Searches the header field that is given by that name.</para>
</listitem>
</varlistentry>
</variablelist>

</sect2>

<sect2 id="filter-action">
<title>Filter Action</title>

<para>The most common use of filters is to sort incoming messages to
certain folders. This can be done by choosing <guilabel>move to
folder</guilabel>. Here is a list of all possible actions:</para>

<variablelist>
<varlistentry>
<term><guilabel>move to folder</guilabel></term>
<listitem>
<para>This will move the message to another folder. You currently 
cannot use <acronym>IMAP</acronym> folders as a target.</para>
<!-- fixme: still correct? -->
</listitem>
</varlistentry>
<!-- TODO: does not exist yet
<varlistentry>
<term><guilabel>copy to folder</guilabel></term>
<listitem>
<para>This will copy the message to another folder.</para>
<note><para>You currently cannot use <acronym>IMAP</acronym>
folders as a target.</para></note>
</listitem>
</varlistentry>
-->
<varlistentry>
<term><guilabel>set identity to</guilabel></term>
<listitem>
<para>This will set <emphasis>your</emphasis> identity if you reply to this
message.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>mark as</guilabel></term>
<listitem>
<para>This allows you to mark the message as read or important (flagged), but
also as forwarded, replied, &etc;</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>set transport to</guilabel></term>
<listitem>
<para>This will set the method of transport (&eg; <acronym>SMTP</acronym>) if
you reply to the message.</para>
</listitem>
</varlistentry> 
<varlistentry>
<term><guilabel>set Reply-To to</guilabel></term>
<listitem><para>Will modify the <guilabel>Reply-To</guilabel> field of this
message. This can be useful for mailing lists that automatically set a Reply-To
which you do not like.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>forward to</guilabel></term>
<listitem><para>Will forward the message to another email address.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>redirect to</guilabel></term>
<listitem><para>Will redirect the message to another email address.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>bounce</guilabel></term> <listitem><para>Will try to
return the message to the sender as undeliverable.</para>

<warning><para>This will only work if the senders email address is
valid. That is <emphasis>not</emphasis> the case for most
spam messages.</para></warning>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>confirm delivery</guilabel></term>
<listitem><para>Will try to return a message to the sender that
indicates successful delivery of his message, if he requested that.</para> <para>This
action allows you to select who will get delivery receipts from
you. Though you can globally enable the sending of delivery
confirmations in the <guilabel>Configure &kmail;...</guilabel> dialog
(<link linkend="configure-security-general"><guilabel>Security</guilabel>
page</link>) we recommended to not send them to everyone, since this
makes tracking of &eg; spam messages very easy for the sender.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>execute command</guilabel></term>
<listitem>
<para>This will execute a program, but will not modify the
message. Specify the full path to the program you want to
execute. &kmail; will block until the program returns. You can feed
the program with the parts of the mail: <symbol>&percnt;0</symbol>,
<symbol>&percnt;1</symbol>, &etc; will stand for files representing
the message parts. For common messages <symbol>&percnt;0</symbol> is the
text, <symbol>&percnt;1</symbol> the first attachment and so
on. Additionally, the whole message is fed into the program's
<acronym>stdin</acronym>.</para>

<!-- fixme: still correct? -->
<warning><para>This currently only works if the message has
<emphasis>at least one</emphasis> attachment. No, not even
<symbol>&percnt;0</symbol> will work in the general
case!</para></warning>

<tip><para> You can enter arbitrarily complex shell commands here,
since &kmail; uses a sub shell to execute the command line. Therefore,
even this command will work (within its limits):
<userinput><command>uudecode</command> <option>-o</option>
<parameter>$(mktemp kmail-uudecoded.XXXXXX)</parameter> &amp;&amp;
<command>echo</command> <parameter>$'\a'</parameter></userinput></para></tip>
<!-- fixme: is this uudecode tip useless now?? -->
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>pipe through</guilabel></term>
<listitem>
<para>This will feed the message to a program. If that program returns
output, the entire message (including the headers) will be replaced
with this output. If the program does not return output or exits
with a return code that's not 0, the message will not change. Specify the full path to the program.</para>
<warning><para>Be cautious with this action, as it will easily mess up
your messages if the filter program does return garbage or extra
lines.</para></warning>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>remove header</guilabel></term>
<listitem>
<para>Will remove <emphasis>all</emphasis> header fields with the
given name from the message. This is useful mainly for removing bogus
<quote>Reply-To:</quote> headers.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>add header</guilabel></term>
<listitem>
<para>If no such field is already present, will add a new header field
with the given name and value to the message. If there is already a
header field with that name, it is overwritten with the new (the
given) value. If there are already multiple headers with the given
name (&eg; <quote>Received:</quote> headers), an arbitrary one of them is
overwritten and the others are left unchanged. This is a known
limitation. You may want to combine this filter with the
<guilabel>remove header</guilabel> filter above to make sure that
there are no other headers with that name in the message.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><guilabel>rewrite header</guilabel></term>
<listitem>
<para>Will scan the given header field, modify its contents and write
it back. The search string is always interpreted as a case-sensitive
regular expression. The replacement string is inserted literally
except for occurrences of <userinput>\n</userinput>,
<userinput>$n</userinput> and <userinput>${nn}</userinput>, where
<userinput>n</userinput> is a positive (single-digit, except for the
third form) number or <userinput>0</userinput>. These constructs are
interpreted as back references to substrings captured with parentheses
in the search string.</para><para>Analogous restrictions as in the
<guilabel>add header</guilabel> action apply here, too.</para>
</listitem>
</varlistentry>
</variablelist>

</sect2>

<sect2 id="filter-examples">
<title>Filter Examples</title>

<para>If I am subscribed to the (general) &kde; List, I could create a
folder for the list (I will call it
<replaceable>KDE-General</replaceable>) and use a filter to
automatically transfer new messages from my inbox to my
<replaceable>KDE-General</replaceable> folder if they are from the
&kde; List. Here is how to create this filter:</para>

<procedure>
<title>Filtering a mailing list</title>
<step>
<para>Try if <menuchoice><guimenu>Tools</guimenu><guisubmenu>Create
filter</guisubmenu><guimenuitem>Filter on
Mailing-List...</guimenuitem></menuchoice> can identify the mailing
list (the name of the list should then appear in the menu item). In
this case, this works and I am presented a filter that has
<quote>X-Mailing-List <guilabel>equals</guilabel>
&lt;kde@lists.netcentral.net&gt;</quote> preset. You select the
desired destination folder from the folder pull-down menu in the
<guilabel>Filter Action</guilabel> group and that's it!</para>

<para>If that does not work, think of a unique way of identifying the
messages you want to filter. The (almost) unique property of my &kde;
List messages is that they always contain
<quote>kde@lists.netcentral.net</quote> in the
<guilabel>To:</guilabel> or <guilabel>CC:</guilabel> field. It is only
almost unique, because this fails for cross-posted messages.</para>
</step>
<step>
<para>Select <menuchoice><guimenu>Settings</guimenu><guimenuitem>Configure 
Filters...</guimenuitem></menuchoice>.</para>
</step>
<step>
<para>Press the <guibutton>New</guibutton> button to create an empty
filter. It will appear as <guilabel>&lt;unknown&gt;</guilabel>.</para>
</step>
<step>
<para>In the <guilabel> Filter Criteria</guilabel> area, select
<guilabel>&lt;recipients&gt;</guilabel> from the first pull-down menu,
<guilabel>contains</guilabel> from the second pull-down menu, and type
<userinput>kde@lists.netcentral.net</userinput> in the text
field.</para>
</step>
<step>
<para>Skip down to the <guilabel>Filter Actions</guilabel> section. Select <guilabel>move to
folder</guilabel> from the first pull-down menu. A new pull-down menu
containing a list of folders will appear. Select the folder that you
want the filtered messages to be transferred to. For this example, you would select
<guilabel>KDE-General</guilabel> from the pull-down menu.</para>
</step>
</procedure>

<para>You may find that you need to use more powerful criteria to
properly filter your messages. For example, you may only want to
filter the &kde; List messages that are written by your friend <replaceable>Fred
Johnson &lt;fj@anywhere.com&gt;</replaceable>. This is where the rest of the
matching criteria section comes into play:</para>

<procedure>
<title>Extending the filter</title>
<step>
<para>Open up the <guilabel>Configure Filters...</guilabel> window and select
the filter you just created.</para>
</step>
<step>
<para>Since you want to filter all messages that have
<replaceable>kde@lists.netcentral.net</replaceable> in the
<guilabel>To:</guilabel> or <guilabel>CC:</guilabel> field
<emphasis>and</emphasis> that are from Fred, check the
<guibutton>Match all of the following</guibutton> radio
button.</para>
</step>
<step>
<para>Now, go to the second search rule and select the following from
the pull-down menus: <guilabel>From</guilabel>,
<guilabel>contains</guilabel>. Now, type
<userinput>fj@anywhere.com</userinput> in the text field.</para>
</step>
</procedure>

<para>You now have a filter that transfers all &kde; List messages
that are from <userinput>fj@anywhere.com</userinput>.</para>
<!-- fixme: trigger with ctrl-j or whenever new mail arrives (unless
<guilabel>Advanced Options</guilabel> are changed. -->
</sect2>
</sect1>

<sect1 id="popfilters">
<title>Download Filters</title>

<para>Download Filters can be used to filter mails from a POP server,
<emphasis>before</emphasis> they are completely downloaded. You can use
it to prevent &kmail; from downloading huge mails and save time this
way.</para>

<para>In the configuration dialog of the POP account you can enable 
download filtering by checking the <guilabel>Filter messages if
they are greater than</guilabel> box. Once you did that, you can specify a size 
which is used as a threshold. Messages exceeding this size will be
checked against the filter rules you defined. If no filter rule
matches, they will be shown in a confirmation dialog and you can
decide what to do with them. The default size for filtering is 50,000
Bytes. This is a good value as the overhead is kept to a minimum.
Every message that is looked at by the filter causes additional
traffic because the header of the message is downloaded twice. The
default action is <guilabel>Download mail</guilabel> to prevent the
loss of messages.</para>

<warning><para>Be careful with the <guilabel>Delete mail from
server</guilabel> option since once a mail is deleted on the server
there is no way to get it back.</para></warning>

<para>With a really good set of filter rules, it is possible that all
messages that exceed the threshold size are automatically tagged
(&ie; downloaded, kept on the server or deleted) and you would never
be bugged by the confirmation dialog. Be careful though, since once a
message is matched by a filter rule, you have no guarantee that you
can change the action before it is executed. Only if there is a
message left that was not matched by a filter rule the confirmation
dialog will show up.</para>

<sect2 id="popfilters-dialog">
<title>The <guilabel>Configure Pop Filter</guilabel> Dialog</title>

<para>Adding filter rules works similar as for <link
linkend="filters">message  filters</link>. On the left hand side you
can manage the existing filters. Use the <guiicon>New</guiicon>
button to add a filter. On the right hand side you can configure
under which conditions the current filter should match. Using <guilabel>Filter
Action</guilabel> you specify what will happen to a message that is 
matched by this rule. The available options are:</para>

<variablelist>

<varlistentry>
<term><guilabel>Download mail</guilabel></term>
<listitem>
<para>Will download the messages matched by the filter, just as any other message
that does not exceed the threshold size.</para>
</listitem>
</varlistentry>

<varlistentry>
<term><guilabel>Download mail later</guilabel></term>
<listitem>
<para>Will tag the messages for later download. This means the messages matched
will stay on the POP server until you choose to download them by
changing the action manually.</para></listitem>
</varlistentry>

<varlistentry>
<term><guilabel>Delete mail from server</guilabel></term>
<listitem>
<para>Will delete the message from the server and does not download it. Once you 
deleted a message from the server, there is <emphasis>no</emphasis> way you can undo this.
Be careful, as rules could match messages you actually want, too.</para></listitem>
</varlistentry>

</variablelist>

<para>The option <guilabel>Always show matched 'Download Later' messages in
confirmation  dialog</guilabel> will cause the confirmation dialog to
show up during mailbox check if at least one message was tagged for
<guilabel>Download Later</guilabel> - even if all messages exceeding
the threshold size were matched by a rule. This option is useful in the
case you have messages matched by a rule and tagged for
<guilabel>Download Later</guilabel>, but you do not get any message
exceeding the size limit for a very long time. Without this option,
the confirmation dialog would never show up and you would never have
a chance to get the queued message by changing the action manually.</para>

</sect2>

<sect2 id="popfilters-confirmation">
<title>The Confirmation Dialog</title>

<para>This dialog shows up whenever you have POP filtering switched
on and  messages were found on the server that exceed the threshold
size you defined for the POP account. Now you have the chance to
decide what you want to do with that message. The options are
<guilabel>Download</guilabel> (green), <guilabel>Download
later</guilabel> (yellow with egg watch) and <guilabel>Delete from
server</guilabel> (red <quote>X</quote>). Be cautious with the delete
option, since once you deleted a mail from the server, there is no
way to undelete it again.</para>

<para>In the <guilabel>Filtered Messages</guilabel> section you can
check the box if you got messages that were automatically tagged for
a certain action (download, download later, delete) by a filter rule.
The checkbox is only enabled if you got some messages that were
matched by a filter rule. Once you check it, a list similar to the
one for the not automatically tagged messages will show up and you 
can change the action for every single message.</para>

<para>Please note that if there is a message exceeding the size
limit, but all messages are matched by a filter rule the dialog will
not show up. One exception occurs if you have checked 
<guilabel>Always show matched 'Download Later' messages</guilabel> in
the <guilabel>Global Options</guilabel> section of the POP filter
configuration dialog. Then the dialog will also show up if you only
have matched messages, but at least one got tagged for
<guilabel>Download later</guilabel>.</para>

</sect2>

</sect1>

<sect1 id="multiple-accounts">
<title>Using Multiple Accounts</title>

<para>Multiple accounts are used to check for messages from more than one email address
and/or mail server. Select <menuchoice><guimenu>Settings</guimenu>
<guimenuitem>Configure &kmail;...</guimenuitem></menuchoice> and click on the
<guilabel>Network</guilabel> page to add or change your account settings. See the
<link linkend="getting-started">Getting started</link> section for more
information on the settings in the <guilabel>Network</guilabel> page.</para>

<para>To check for messages from a particular account, use the
<menuchoice><guimenu>File</guimenu><guimenuitem>Check Mail
In</guimenuitem></menuchoice> submenu to select the account to check
for mail. You can also press the mouse button on the <guiicon>Check
Mail</guiicon> icon for some time to get a list of accounts.</para>

</sect1>

<sect1 id="pgp">
<!-- This section is from Andreas Gungl, 2000-05-21, updated 2002-10-06 by Ingo Kloecker -->
<title>Signing and Encrypting Messages with <application>PGP</application> 
or <application>GnuPG</application></title>

<para>This is a short introduction on how to setup &kmail;'s
<application>PGP</application> (<application>Pretty Good Privacy</application>) support. 
It will give some hints on the use of
<application>PGP</application> too. It is written for people who are beginners in
this area. If you are familiar with the use of <application>PGP</application>, you can
skip most of the steps. This documentation (and the &kmail; user interface) 
generally talks only about  <quote>PGP</quote>, but it applies to 
both <application>PGP</application> and <application>GnuPG</application> 
(<application>GNU Privacy Guard</application>), 
although some <application>GnuPG</application> command line parameters 
may be different.</para>

<para>Please
also check out the <link linkend="pgp-faq">&FAQ; item about
<application>PGP</application></link>.</para>

<!-- note: this is partly copied above: -->
<warning><para>Attachments will not be encrypted if you are using 
the built-in OpenPGP support. To encrypt attachments, you have to install
and configure <link linkend="configure-security-plugins">encryption plugins</link>.
Then you can decide for each attachment if it should be encrypted or not.
</para></warning>

<warning><para>&kmail; has to rely on <application>PGP</application>'s
output. This output is often different between different versions of 
<application>PGP</application>, so it is important that you test if encryption
really works with your setup before you start using it seriously. &kmail; might
<emphasis>not</emphasis> warn you if something fails. You better enable 
<guilabel>Show signed/encrypted text
after composing</guilabel>.  </para></warning>

<para>To setup and use <application>PGP</application> support in &kmail; it is
necessary to have <application>PGP</application> installed and set up
properly. Of course we cannot give you a full introduction of
<application>PGP</application> here. We will only mention the steps you have to
do to get <application>PGP</application> going. For details you should have a look at 
the excellent  <application>PGP</application> documentation 
or <ulink url="http://www.gnupg.org/docs.html#guides">The GNU Privacy Handbook</ulink>.</para> 

<para>It is certainly a good idea to study this documentation as well as an
introduction into public key cryptography (&eg; out of the
<application>PGP</application> 6.5.x package). There you can learn a lot about
the basic concepts, which will help you to understand what is going on. As well,
many security related issues you should know about are discussed there.</para>

<para>Now let's start.</para>

<sect2 id="pgp-preconditions">
<title>Preconditions</title>

<para>&kmail; expects that your <application>PGP</application> binary is called
<command>pgp</command>.  In case of <application>GnuPG</application>, it expects
the binary to be called <command>gpg</command>. If that is not the case for you,
just make a symlink.</para>

<para>If you have not done so, you have to generate a key pair (secret and public
key) for your identity. You must do this at the command line: use
<userinput><command>pgp</command> <option>-kg</option></userinput>
resp. <userinput><command>gpg</command> <option>--gen-key</option></userinput>.  &kmail;
has no internal support for <application>pgp</application>'s key generation at
this time. The identity (normally your name followed by your email address
within brackets, such as <userinput>John Doe
&lt;john@example.com&gt;</userinput>) and your passphrase are important for the
co-operation between &kmail; and <application>PGP</application>.</para>

</sect2>

<sect2 id="pgp-settings">
<title><application>PGP</application> Related Settings in &kmail;</title>

<para>Select the <guilabel>OpenPGP</guilabel> tab on
the <guilabel>Security</guilabel> settings page. There you will find the
following options:</para>

<variablelist>

<varlistentry>
<term><guilabel>Encryption tool</guilabel></term>
<listitem>
<para>Here you can choose if you want to use <application>PGP</application>,
<application>GnuPG</application> or no encryption
software at all. Of course the program you select has to be
installed on your system. It is also important to select the correct
version.</para>
</listitem>
</varlistentry>

<varlistentry>
<term><guilabel>Keep passphrase in memory</guilabel></term>
<listitem>
<para>When this option is off, &kmail; will ask for your passphrase each
time you sign a message (before sending) or select an encrypted message.
If you turn this option on, &kmail; will remember your passphrase from
after your first successful input until you finish your &kmail; session. The
passphrase is stored in memory and not written to the hard disk.
If you use one of the Crypto-Plugins or if you use <application>GnuPG</application>
with the gpg-agent then an external program will ask for your passphrase and
optionally remember it for some time.</para>
</listitem>
</varlistentry>

<varlistentry>
<term><guilabel>Always encrypt to self</guilabel></term>
<listitem>
<para>If this option is off and you want to send an encrypted message to somebody,
then you cannot read this message any longer after you have composed and
encrypted it. Turn this option on to keep sent encrypted messages readable for
you too.</para>
</listitem>
</varlistentry>

<varlistentry>
<term><guilabel>Show signed/encrypted text after composing</guilabel></term>
<listitem>
<para>This will show you the result of encrypting and signing before the message
gets sent. This way you can still cancel sending if encrypting failed. It is
strongly recommended to use this option.</para> 
</listitem>
</varlistentry>

<varlistentry>
<term><guilabel>Always show the encryption keys for approval</guilabel></term>
<listitem>
<para>This will always open a dialog that lets you choose the keys used for
each recipient when you are sending an encrypted message. If this
option is off, &kmail; will show this dialog only when it cannot
find a key for a recipient or when there are conflicting or unset encryption
preferences.</para> 
</listitem>
</varlistentry>

<varlistentry>
<term><guilabel>Automatically sign messages using OpenPGP</guilabel></term>
<listitem><para>This lets you toggle whether to automatically sign your messages
by default. Of course it is still possible to send unsigned messages by deselecting
the icon in the composer window.</para> 
</listitem>
</varlistentry>

<varlistentry>
<term><guilabel>Automatically encrypt messages whenever possible</guilabel></term>
<listitem><para>If this option is on, &kmail; will automatically encrypt messages
with the built-in OpenPGP support or the PGP/MIME-Plugin provided that
for every recipient a trusted PGP key is found in your keyring and
provided that you did not tell &kmail; not to encrypt messages send to
certain recipients. If in doubt &kmail; will ask whether the message
should be encrypted or not.</para></listitem>
</varlistentry>

</variablelist>

<para>Now that you have setup the encryption tool you have tell &kmail; which
OpenPGP key you want to use for signing and for encrypting messages.
To do this go to the <link linkend="configure-identity">Identities configuration</link>
and set the key that should be used on the <guilabel>Advanced</guilabel> tab of the
identity configuration.</para>

<para>Now you are able to sign outgoing messages. To let people send you
encrypted messages and to let them verify your signature you
must send them your public key or upload your public key to a public
<application>PGP</application> key server so that they can fetch your key from there.
To send encrypted messages to other people or to verify their signed
messages you will need their public keys.  You can store your public key(s) on a
public <application>PGP</application> key server such as <ulink
url="http://www.cam.ac.uk.pgp.net/pgpnet/">http://www.cam.ac.uk.pgp.net/pgpnet/</ulink>.</para>

</sect2>

<sect2 id="pgp-sign-your-messages">
<title>Sign your Messages</title>

<para>You compose your message as usual in the composer
window of &kmail;. Before you send the message, check the <guiicon>Sign Message</guiicon>
icon on the toolbar of the composer window. Then, you can send
the message. The identity you are using to write the current message needs to 
be connected to an <guilabel>OpenPGP Key</guilabel> in the <guilabel>Identity</guilabel>
section of the <guilabel>Configure</guilabel> dialog.
To sign the message, &kmail; needs to know your <application>PGP</application> 
passphrase. If you did not select <guilabel>Keep passphrase in memory</guilabel> in the
<guilabel>Security</guilabel> section, &kmail; will ask you for it.  On the
other hand, if you have already given the phrase to &kmail;, it will sign the
message without any further prompt.</para>

</sect2>

<sect2 id="pgp-encrypt-your-messages">
<title>Encrypt your Messages</title>

<para>To send an encrypted message to somebody of whom you have a
public key, you simply create the message in the composer window.
Before you send the message, check the <guibutton>Encrypt
Message</guibutton> button in the toolbar of the composer window. Note
that you might not have to check the button if <guilabel>Automatically
encrypt messages whenever possible</guilabel> is selected in
&kmail;'s configuration (see <link linkend="pgp-sign-your-messages">above</link>).
Then send the message.</para>

<para>
If you checked the <guilabel>Encrypt Message</guilabel> button and &kmail;
cannot find a matching key for a recipient, it will display a list containing
all available keys in the <guilabel>Encryption Key Selection</guilabel> dialog.
If &kmail; finds more than one trusted key for a recipient, it will
display a list containing all matching keys for this recipient. In both
cases you can select the key(s) which should be used for encrypting
this message for the recipient in question.
Using the <guilabel>Remember choice</guilabel>
checkbox you can save your selection for future messages.</para>

<para>If you are using a key for the first time or if there are conflicting
Encryption Preferences or if <guilabel>Always
show the encryption keys for approval</guilabel> is selected in the
<guilabel>Security</guilabel> section of &kmail;'s configuration dialog,
the <guilabel>Encryption Key Approval</guilabel> dialog will appear.
Here you can select different keys for the recipients and you can also 
set the <guilabel>Encryption Preference</guilabel> for each recipient.
The default option, <guilabel>Encrypt whenever encryption is
possible</guilabel>, will automatically encrypt your message if there is a 
trusted key for each recipient.</para>

<para>As mentioned above, you will not be able to read your own encrypted sent
messages if you do not check <guilabel>Always encrypt to self</guilabel> in the
settings' <guilabel>Security</guilabel> page.</para>

</sect2>

<sect2 id="pgp-send-your-public-key">
<title>Send your Public Key</title>

<para>Prepare a message to the person you want to send your public key to. Then
choose in the composer window's menu
<menuchoice><guimenu>Attach</guimenu><guimenuitem>Attach My Public
Key</guimenuitem></menuchoice>. This will attach the public key you
defined for the current identity to the message. Now you can send the message.</para>

<para>Remember that it is not safe at all if you sign the message to make sure
that the receiver will get the correct key. There can be a man-in-the-middle
attack, as somebody can change the key and sign the message with that other
key. That is why the recipient should verify the attached key by checking the
key's fingerprint against the one he got in a secure way from you. Have a look
at the <application>PGP</application> documentation for further details.</para>

</sect2>

<sect2 id="pgp-you-got-an-encrypted-message">
<title>You got an encrypted Message</title>

<para>All you have to do is to select the message in &kmail;. You will be
prompted for your passphrase. Then &kmail; will try to decrypt the message and
show you the plain text if the message had been encrypted with your public
key. (If not, then you will not be able to read it.) &kmail; stores the messages
encrypted, so nobody can read these messages without knowing your passphrase.</para>

</sect2>

<sect2 id="pgp-receiving-a-public-key">
<title>Receiving a Public Key</title>

<para>You can receive a public key as an attachment or via http, ftp or a floppy.
Before you can use this key to encrypt a message to the owner of the
key, you should verify the key (check its fingerprint or look for
trusted signatures). Then you can add this key to your public keyring
by typing <userinput><command>pgp</command> <option>-ka</option>
<replaceable>filename</replaceable></userinput> at the command line if you are using 
<application>PGP</application> or by typing 
<userinput><command>gpg</command> <option>--import</option>
<replaceable>filename</replaceable></userinput> at the command line if you are using
<application>GnuPG</application>. If the key is not certified with a trusted signature 
you cannot use it to encrypt messages unless you have signed the key with your key.
</para>

</sect2>

</sect1>
<sect1 id="using-kmail-authors">
<title>Section Authors</title>

<para>This section written by:
Daniel Naber <email>daniel.naber@t-online.de</email> and
David Rugge <email>davidrugge@mediaone.net</email>.</para>

<!-- TRANS:CREDIT_FOR_TRANSLATORS -->

</sect1>
</chapter>
