Error message when changing server name

This is what happens:

1. I go to the Network Identification tab and try to change the name of the server from “data” to “server2”
2. It asks for a username and password. I enter an account with admin privleges.
3. An error message pops up saying this:
“The following error occured attempting to rename the computer to ‘server2’:
The credentials supplied conflict with an existing set of credentials.”

Any ideas on what this means and how to resolve it?

-Matt