Problem
Emails to a new email domain are always sent to the postmaster.
Investigation
Send an email from an external mail account. Then check the /var/log/mail.log and the mail header after the mail was delivered to the postmaster.
Solution
If the mail header contains the following message, fetchmail cannot match any mailserver usernames or localdomain addresses, the mail will be send to the local postmaster instead.
X-Fetchmail-Warning: Empfängeradresse test@mynewdomain.com stimmt mit keinem lokalen Namen überein
The solution is to add the domain to the multi-drop fetchmail configuration, for example:
poll http://mymailserver.net proto POP3 localdomains myolddomain.com mynewdomain.com envelope X-Rcpt-Original user ‚xyz' with pass ‚***' to * here nokeep fetchall ssl