Yes, found something.
It is a new domain freshly started. The company that is serving me this service is also an ISP and give people who buy a domain automaticly a mailbox.......
So, my mail was going to them and not my own server.
Now I have fit in (can do that myself) mx1 record into my dns records (I didn't wanted to use my own dns server).
So now I have to wait until the dns records are being updated.
In the meantime my mailqueue is flotting. I don't get it empty.
Still the same error? Peace of mail.log.
Nov 5 21:46:12 server1 postfix/smtp: 42A6A82CE5: to=<firstname.lastname@example.org>, orig_to=<root>, relay=none, delay=8770, delays=8770/0.19/0.01/0, dsn=4.4.1, status=deferred (connect to 127.0.0.1[127.0.0.1]:10024: Connection refused)
Nov 5 21:46:12 server1 postfix/error: 9AEC082CEC: to=<email@example.com>, orig_to=<root>, relay=none, delay=4570, delays=4569/0.32/0/0.05, dsn=4.4.1, status=deferred (delivery temporarily suspended: connect to 127.0.0.1[127.0.0.1]:10024: Connection refused)