On Mon, 6 Aug 2001 10:13:55 -0400
Jan Schaumann <jschauma(_at_)netmeister(_dot_)org> wrote:
The "xyz is not a mailbox" error I've seen several times, but I don't
remember the fix. I believe it's a mutt-thing, so you might consider
checking on comp.mail.mutt et al.
I often got this error while testing Procmail recipes, and I fixed this error
by removing /var/spool/mail/username.
A new mailbox was created when the next message arrived and Mutt did not
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