I opened this question under the general topic of "Email/GroupWare" but have had no responses. Therefore I am opening the same question under the Exchange Server topic. I will award the points from both to whoever is able to help me resolve this problem ASAP!
We are experiencing a strange problem whereby one of our customers seems to be unable to send us emails. The error message they get back is as follows:
Status: 5.0.0 (permanent failure)
Diagnostic-Code: smtp; 5.4.7 - Delivery expired (message too old) 'DNS Soft Error looking up xxxxx.com (MX) while asking 188.8.131.52. Error was: ServFail' (delivery attempts: 0)
Reporting-MTA: dns; ironport.ccccc.com
Has anyone had any experience in solving this problem?
Is this something on our end or the customer's end? (It appears they have setup their own DNS servers.)