Plusnet Service

We are currently investigating a problem with incoming mail being rejected by mail platform. Affected emails may be bounced to the sender with a message similar to that below :
---
Your message cannot be delivered to the following recipients:

Recipient address: postmaster@username.plus.com
Reason: Remote SMTP server has rejected address
Diagnostic code: smtp;550 RCPT TO:<postmaster@username.plus.com> Relaying not allowed
Remote system: dns;mx.core.plus.net (cp3a.criticalpath.priv ESMTP Service [7.3.118.8] ready)

If you were logged in to the portal, you could associate your username with this problem.

This problem has been passed to a network engineer for investigation.

We have identified the cause of the problem and disabled the servers that are the root cause.

We will be investigating why the problem reoccurred further, however this problem will be downgraded as it no longer affects customers directly.

We have identified that this problem may be re-occuring albeit on a smaller scale with a smaller sub-set of customers. Our networks team are currently investigating this.

The accounts who have been reported are accounts that are in queued-destroyed status, ie they are no longer active accounts, hence the email is validly bouncing.

I am downgrading this problem again so we can continue to monitor yesterday's issues on it.