I have a HUGE problem. I can't believe I did this, but I was changing some group policies, in order to allow certain groups of users to log in via terminal services. I was successful in this, however those are the ONLY users that can now "Log in Locally" to the domain controller. The Administrator account is unable to log into that computer! I am only able to login to the domain controller using some non-privileged accounts. These are accounts which do not have permission to change any security policies or add the administrator to the group of users currently able to log in.
Specifically, what I did was follow "Method 1" of Microsoft's Article: 260370 "How to Apply Group Policy Objects to Terminal Services Servers". http://support.microsoft.com/?kbid=260370
This article had me create a new OU, and move my server from the "Domain Controllers" OU to one that I created. Then, add group(s) that could log on locally. It did not say, nor did I specifically add the "Administrators" group.
If anyone has ANY suggestions please let me know. This is one of the most important servers in my network. I still can't believe what I did! Thanks for ANY help at all.