I have a very strange problem after moving my netwave.be domain from WebHost4Life to Arvixe.

I configured several email adresses, like [email protected] and [email protected].

For POP3 I can use mail.netwave.be, a mailserver hosted by Arvixe.

However, for SMTP I have to use relay.skynet.be. Skynet (Belgacom) is one of the biggest internet providers in Belgium and blocks smtp requests to external mailservers. So for years I've been using relay.skynet.be to send my messages using [email protected] as the sender. The worked perfectly.

After moving my domain to Arvixe, this is no longer the case.

I can send emails to people, no problem. I have received emails too, so I suspect that's ok too.

But I can't send emails from one user of my domain to another user.

For example, if I send a mail from [email protected] to [email protected], relay.skynet.be picks up the mail just fine. A few seconds later, I get a 'Delivery Status Notification (Failure)' mail that contains:

Reporting-MTA: dns; mailrelay012.isp.belgacom.be

Final-Recipient: rfc822;[email protected]

Action: failed

Status: 5.0.0 (permanent failure) Remote-MTA: dns; [69.72.141.4]

Diagnostic-Code: smtp; 5.1.0 - Unknown address error 530-'SMTP authentication is required.' (delivery attempts: 0)

Like I said, this only seems to be the case when both the sender and recipient are adresses of a domain hosted by Arvixe.

I have serveral accounts not related to Arvixe at all. I can use relay.skynet.be to send mail to [email protected] using these accounts. Likewise, I can use relay.skynet.be to send mail from [email protected] to these accounts. but not from one Arvixe account to another.

I hope I have clearly outlined the problem and someone will be able to help me.