When navigating to cPanel >> Spam Filters and attempting to perform any modification changes, you may encounter a similar error:
Error: “/usr/bin/doveadm” reported error code “68” when it ended:
doveadm($USER): Error: Mailbox INBOX.$USER@domain_tld:
Failed to lookup mailbox status: Mailbox doesn't exist:
The error indicates that while attempting to load the configurations for certain email users, it was found that the user did not exist.
This can happen if an email account was not removed properly or something caused the removal process to leave cruft behind.
First, you want to make sure that the email address reported in the error log is an account that was meant to be removed.
If the reported failure describes an account that should exist, then a restoration from a backup will need to take place, as this error indicates that the symlink for the mailbox no longer points to a valid path.
If the account in question was meant to be removed, then you will simply need to unlink the symbolic link that was left behind.
The easist way to located broken symbolic links is with the following command:
find /home/$USER/mail/ -maxdepth 1 -xtype l
This will print any broken links which can then be safely removed using the "unlink" utility.