OK, so we send out a few hundred emails to clients each morning, and most are fine - many go to deifferent recipients on one domain - say 10 to domainA, 20 to domainB, 5 to domainC, etc..
Thing is, while most are OK, those to a cuople of the domains are getting bounced back with a mesage "Unable to obtain any valid MX records for the domain."
What are we supposed to do about this? Our domain/IP hasn't changed - just the mail server software, (which is now AMS)....
regards
Phil