We have recently changed some domain MX records and naming servers for two domains that are on the same exchange server up until then everything worked ok, the reason for change is we needed to change the hosting around because one domain was using a no-ip.org host for its A Record for some reason while the other was configured via the domain host.
We have two domains I domain1.co.uk and domain2.co.uk (with domain 1 being the primary domain) from what I can see all mail is being received correctly on this domain by the internal users. domain2.co.uk is not receiving any e-mails whatsoever when I try and submit a test e-mail nothing is received and a bounce back is not received either although some further testing on Microsoft Remote Connectivity analyser suggests that this may be a relay error. domain2.co.uk has been working before as I have quite a few users using this domain to receive e-mails. From what I can see sending e-mails isn't a problem.
I would appreciate a really quick response on this as I'm completely at loss. I'm sure its something simple but I don't know what it is.