because it didn’t work like it should, today I sat down and tried to fix it – with success :-)
My config now sends all mail which is sent on my server to my external account at domainfactory. So I don’t need to check if there are any errors occured, because the errror mail will be forwarded.
How does my config look? I’ll only post the relevant parts.
mailbox_transport = msmtp
default_transport = msmtp
msmtp unix - n n - - pipe
flags=. user=msmtp argv=/usr/bin/msmtp -C /etc/msmtprc -a df firstname.lastname@example.org
This works like a charm, but don’t use it, if you have a server with more than one user or if you wan’t to sent mails to other mailadresses than email@example.com as well. Anyway, you could use at least the /etc/msmtprc.