A D Issue

Have an Exchange 2003 server in an environment with a DC. The issue is that there are NDRs coming every 3 mins in the Event Viewer of the Exchange Server. Is it DNS resolution or some kind of looping.
Also from time to time in Exchange System Manager on the same Exchange 2003 Server. It is giving the error Specified Domain either does not exist or could not be contacted.
Facility:Win 32
ID No: c007054b
Microsoft Active Directory. System Extension.

Need some help resolving these issues ASAP. Urgent because the NDRs are stacking up.