Postfix ERROR! - Need fix for this!
I've been trying to understand why I've been having so much problems with postfix since I installed ISPConfig and created mail-accounts through it.
It turns out ISPConfig doesn't make an entry with only the domain which is demanded when using smtp-auth etc.
A line like this should be added by ISPConfig when creating the first account on a new domain:
That's all that's required but without it all you'll get is a whole lot of 554 : Relay access denied