Message folders serve as an organizing tool for your messages. By default, all message folders are stored in the Mail folder in your home directory. The inbox, outbox, sent-mail, and trash folders are created when KMail is started for the first time. These folders have the following functions:
inbox: KMail stores new messages here (unless a filter has been defined).
outbox: Messages to send are stored here.
sent-mail: Copies of all e-mails sent are stored here.
trash: Stores deleted e-mails.
Using 15.3: “Creating New Folders”). To create a subfolder, select the parent folder from the drop-down list . Specify the folder type, any mailing list associated with it, and an expiry date after which the messages are marked for deletion. Furthermore, you can select an identity or display a certain sender or recipient.-> , you can create additional folders for organizing your e-mail messages. Enter the name of the new folder in the dialog that opens (see Figure
To move messages from one folder to another, highlight the message to move then press M or click-> . In the list of folders that appears, select the folder to which to move your messages. Messages can also be moved by dragging the message from the upper window and dropping it into the appropriate folder in the left window.
To remove all the messages from a folder, click-> . All messages located in the folder are then moved to the trash.
Messages are not deleted permanently until you empty the trash.