Little history: because of a new gigbit network I got a gigabit network card, it didn't work so I went back to the old card. Got back to the perfect setup (Debian Sarge + ISPConfig) and changed the /etc/network/interfaces back to how it was in the beginning. Now all of a sudden all emails get bouced with this message: Code: This is the Postfix program at host server.***.nl. I'm sorry to have to inform you that your message could not be be delivered to one or more recipients. It's attached below. For further assistance, please send mail to <postmaster> If you do so, please include this problem report. You can delete your own text from the attached returned message. The Postfix program <(mailaccount)@server.***.nl> (expanded from <***@***.nl>): mail for server.***.nl loops back to myself Please help me out on this!