KMail add local mbox folder
Go to Configure / Accounts. Under Receiving select Add / Custom account and choose Mbox.
Under “File name”, type in the path to the file in /var/mail/
(browsing doesn’t work). Leave
“Display Name” empty.
An akonadi_mbox_resource_*
entry is created. Select “Restart” on it, and ignore the error message.
Restart KMail. The entry should now appear as the mbox file name.