Unrouteable mail domain - Error reported


Well-Known Member
May 3, 2003
One of my customers has reported getting an error when e-mailing someone they have previously e-mailed without a problem.

The error is:

[email protected]
SMTP error from remote mail server after RCPT TO:<[email protected]>:
host c-l-d.net []: 550-Verification failed for <[email protected]>
550-unrouteable mail domain "customerdomain.co.uk"
550 Sender verify failed

If I do an 'exim -bt' for either my customers e-mail address or one of mine (on the same server) I get the following error:

[email protected] cannot be resolved at this time: All deliveries are handled by MailScanner

Does anyone know what the problem might be, or what my next step should be ?

Thanks in advance,