Message Folders are used to organize your email messages. When you first start KMail the inbox, outbox, sent-mail, trash, drafts and templates folders are created. These folders each have special functions:
Where KMail by default puts your new messages when you ask it to check your mail.
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 Send icon in the composer window instead.
By default copies of all messages that you have sent are put into this folder.
By default all messages that you have moved to trash are moved into this folder.
Contains messages you started to edit but then saved to this folder instead of sending them.
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 → . The folder properties 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 from the context menu.
To move messages from one folder into another, select the message(s) you want to move and press the M key or select → . 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 Message list to a folder in the Folder list.
If you want to clear all of the messages out of a folder choose → . You can use → to remove a folder and all its messages and subfolders.
The folder's Properties 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 inbox etc. Default folders also cannot be moved or renamed.
Rename a folder by changing the entry in the Name: field.
Check Act on new/unread mail in this folder if you want to be informed about new mail that arrives in this folder. Setting this option is for example useful for the folder where you move all detected spam messages to.
Check Keep replies in this folder if you want replies to messages in this folder to be filed also into this folder rather than into a special sent-mail folder.
Check Hide this folder in the folder selection dialog if you do not want this folder to be shown in folder selection dialogs, such as the dialog.
With the Sender identity option you can set the default identity that should be used for new messages if this folder is selected. Replies to messages that were sent directly to you will still default to the message's “To” address if an according identity is found.
The Use custom icons option lets you choose icons that are different from the default ones in the folder list.
With Show columns you can set the visible columns in the header pane to Default, Sender or Receiver. This is useful if you use a folder to save your own sent messages.
In the Message List section you can select and configure an Aggregation and Theme for this folder different from the default configured in KMails settings. For more details see the Message List tab in the Appearance page.
Deselect Use options from parent folder or account to set folder-specific options for synchronizing and retrieval of messages.
On this tab you can define folder-specific templates for your custom folders. For more details see the Standard Templates tab in the Composer page
From the context menu of a folder select to open the Mail Expiry Properties dialog. Here you can select what should happen with old messages in this folder. If you enable to expire old read or unread messages in this folder then KMail will regularly, depending on your choice, either delete old messages or move old messages to another folder.
Messages that are deleted during expiration of old messages cannot be restored, so be careful with this setting.
If you are going to use the folder for a mailing list open the Mailinglist Folder Properties dialog with → from the menu. Then you should check Folder holds a mailing list to associate this folder with the mailing list. Next you should click on Detect Automatically. KMail will then try to guess some information about the mailing list from the currently selected message. If KMail could not determine some addresses then you can add the missing information manually. To do this first select the Address type for which you want to add an address. You can choose between:
- Post to List
This address is used for sending messages to the mailing list. This is usually an email address.
- Subscribe to List
This address is used for subscribing to the mailing list. This can be an email address or the address of a webpage.
- Unsubscribe From List
This address is used for unsubscribing from the mailing list. This can be an email address or the address of a webpage.
- List Archives
This is the address of the archive of the mailing list. This is usually the address of a webpage.
- List Help
This address is used for requesting help for this mailing list. This is usually an email address.
After selecting the appropriate Address type you enter the email address or the address of the webpage and then click on Add. With Remove you can remove addresses.
If all addresses have been added then you can execute an action, e.g. go to the list archives, by selecting the appropriate Address type and then clicking on Invoke Handler. If there is an email address and an address of a webpage for the desired action then you will have to select the Preferred handler prior to clicking on Invoke Handler. Select KMail; if you want to send a message to the email address and select Browser if you want to go to the webpage.
Alternatively to invoking the handler for Post to List you can send a new message to the mailing list via →
Here you can manage the access control lists (ACLs) of IMAP folders.
The currently active ACL is shown in the list. It consists of pairs of User Ids and the Permissions granted to users identified by that User Id.  ACLs are settable per-folder.
As with everything else when using disconnected IMAP, you need to sync with the server for the changes to be transferred to the server.
IMAP ACLs define a lot of fine-grained permissions that you can grant or deny other users. For the sake of clarity, KMail will present them as the following five categories that you can choose from (see Table 3.1, “ ACL Rights Summary ” for the details if you already know IMAP ACLs).
Grants the users identified by User Id no rights at all. This is also the default for users not explicitly (or implicitly, as a group) listed in the ACL. These users will not see this folder in the list of IMAP folders presented to them by their mail clients.
Grants the users identified by User Id reading rights for this folder. This also includes the ability for their mail clients to mark mails as read and store this information on the server.
These users will see this folder in the list of IMAP folders presented to them by their mail clients.
Use this to create a shared folder that others can read, but not modify.
If you were the editor of a company's news letter, you could create a folder for the purpose of distributing the news letter, grant everyone reading rights, and save the letter to this folder instead of sending it out by email to a catch-all address.
(also known as Post)
Grants the users identified by User Id reading (see above) and posting rights for this folder.
Use this to create a shared folder that others can read and post messages to, but cannot otherwise modify.
If you wanted to create a company-wide discussion forum, instead of using a web-based form or a separate company-private usenet server, you could create a bunch of folders (one per topic), and grant everyone reading and posting rights. Instead of posting to an NNTP server or writing their messages into a web form, people would just write emails and store them in the folder suiting the topic of the message.
Grants the users identified by User Id reading, posting (see above), and writing rights for this folder.
The right to write to a folder includes deleting of messages, creating subfolders, and storing other attributes than read/unread on the server (e.g. answered).
Use this to create a shared folder that everyone has (almost, see All ) the same rights for.
In the Append example, you could assign write rights to a group of people acting as moderators, which would then be able to remove off-topic posts, and create sub-topic-folders for high-traffic folders.
Grants the users identified by User Id reading, posting, writing (see above), as well as administration rights, i.e. the right to modify the ACL of this folder.
This is the default set of rights for the owner of a folder.
Table 3.1, “ ACL Rights Summary ” summarizes the IMAP ACL rights associated with each permission level.
Table 3.1. ACL Rights Summary
 Note that a single User Id might refer to more than one user. Depending on the IMAP server and its configuration, there may be User Ids that correspond to groups of users, anonymous users, or any user. Consult the manual of your specific IMAP server implementation for more information.
 Every user has their own list of read mail, so none of your unread mails will suddenly be marked as read just because someone else has already read them.