We have 1 exchange 2003 server. Out of nowhere one day we stopped receiving emails from some, but not all, domains (internal emails worked fine). Also, outgoing emails seemed to get stuck in queues for longer than normal.
I checked message tracking for expected incoming emails but found nothing. My first guess was that there was a DNS problem. Our domain hosting company assured me that all DNS settings were correct, but our ISP said we were missing a reverse DNS record. They added the record at that time. According to the ISP there was no maintenance or configuration changes of any kind recently and more than likely the reverse dns was just never there. We have been using this ISP for months, and never had any problems previously–could that be true?
Atleast a week later most email communication is working fine, but still some domains cannot reach us or we recieve emails up to a day and a half late. I am certain this must be DNS related as I had someone send a bounceback message to my personal account which stated: “Failed to connect to the recipients mail server. No DNS information was found for the ‘midbrook.com’ domain.”
Can anyone offer an explanation of what might have caused this problem out of nowhere? What about a solution for the domains that still can’t reach us or outgoing emails that are stuck in the queues longer than they should be? Also, the outgoing emails that are in the queue longer than normal are going to the domains we have trouble receiving from.
Thanks in advance!
