Exchange server 2010 joining a 2003 R2 DC

[TB64]

We have an exchange server version 2010 which is joined to a 2003 R2 DC. the problem is and its my fault I deleted the computer name in users/Computers. I readed it no problem but the exchange server say it cant find and domain controllers. What I want to know is when you right click the name of the exchange computer and go to member of

what should I expect to see in there. What should it be a member of.

[TB64]

I have sorted this.