I gave a mailcow instance running since a couple of weeks.
Now I am moving my domains and emails to mailcow, which worked fine so far but recently I encountered a strange problem:
In my old setup I have a mailrelay server which receives mails from various servers and send them via smtp to an email.
This used to work fine until I moved my emails to mailcow. Now I get the error message 554 5.7.1 which means I am not allowed to relay the mails.
the sender from is root@my-domain
the sender to is admin@my-domain
i have a postbox mailrelay@my-domain which I use for smtp.
I was expecting, creating an alias root@my-domain to admin@my-domain whould solve the problem but this does not work.
Also an alias root@my-domain to mailrelay@my-domain does not work.
Any ideas how to solve this?
Thanks and Kind regards