I have a Windows 2008 R2 Server that’s a member of a domain, when I add a domain account to local administrators user group the account resolves but as soon as I apply it disappears. If i try to add it again it says the account already exists but i can see it in the group. This account can log in to the server but cannot perform anything since it gets access denied even to opening a cmd or notepad application. Thanks in advance

Is in the permission view one ore more SID (basicly long numbers) visible? If so there might be something wrong with the computer's authentication. To resolve this you can try removing the server from the domian and rejoining it. For futher troublehooting: can you add any other account to the local admins? Does the same apply for local account? Are there any policies in place that restrict the local admins?MCSA/MCTS/MCP

Thanks SenneVL for the reply, I have already removed and readded the server to the domain but it didnt fix the issue and no any account I try to add behaves the same. The only account thats visiable is the administrator account.

Have you checkd the policies in affect on this machine? Maybe a policiy was defined restricting the local admins?MCSA/MCTS/MCP

I also consider if it is a group policy setting. Can you re-add the same account after reboot? I mean will you still get the message "account already exists" after reboot? Meanwhile, what account are you using to add the domain account to admin group, another domain account or a local admin account? If you are not the domain admin, you can try to confirm with admin group about this issue. Shaon Shan| TechNet Subscriber Support in forum| If you have any feedback on our support, please contact tngfb@microsoft.com

after the reboot i still get the account already exists msg. I am also using (administrator) a domain account to add the domain user accounts.

Have you tried to logon locally to add an admin account? Meanwhile, you may try to run a gpresult /r to see the applied policies and check if there is any restrict related to admin group.Shaon Shan| TechNet Subscriber Support in forum| If you have any feedback on our support, please contact tngfb@microsoft.com

Seems to be an issue with the VM template that I was using, I recreated the VM's without using the Image and got the issue resolved. Thanks all for the efforts