I am currently trying to run some tests for OCS 07 R2 and have set up everything, however I am currently working on 2 laptops so that I can create an enviroment of having two different machines using the shared desktop option, but on one machine I am unable to login to OCS because it says that the server is unavailable. Everythying is up and running on the other laptop, and I can even sign in using the other username on this laptop, but when I try to log on to the other machine it gives me that error. I have checked the DNS A record config and everything is OK, could it possibly be the actual laptop that is having troubles?
Did you resolve this issue? If not, enable Windows Event logging in communicator on the problematic workstation to get more info on what's happening during sign-in attempts. That can be turned in Tools > Options > General > Logging. Jeff Schertz, PointBridge | MVP | MCITP: Enterprise Messaging | MCTS: OCS