I have a Windows 2003 SP2 Enterprise server with Exchange 2003 SP2 serving about 10 users only.
I was trying to migrate to Windows Server 2012 Essentials. After I setup the new server and did the migration, I found that Essentials 2012 doesn't support Exchange as 2011 does. Then I demoted the new 2012 and removed it from the domain and re-formated it to install the Windows 2008 R2 on it.
Their are two problems now:
1. Emails are no longer working.
2. I receive an error when a new computer tries to join the domain saying to check DNS settings. DNS settings are correct and the old DC is acting well as a DNS server for forwarding DNS requests to the outside.
I have a backup of the old DC 2003 but I will lose some data if I restore it.
What shall I do now?