DNS problem

I am using Windows Server 2003. One server is Domain Controller with DNS installed. Other server to run Exchange 2003 to host. Getting error 7062 that reads that packets are being addressed to myself in Event Viewer.
Because of this error unable to load Exchange on the second server. Not able to find Active Directory so won’t run Forest Prep.
How do I solve the DNS problem to be able to install Exchange 2003 and host mail on the second server?