Windows 7: Only account doesn't have Permissions to view LAC Properties

I have a user who has a machine with a single local account on it. They can log in using the account and we need them to edit their TCP/IP settings in order to have them connect to us and join our domain. As I said, there is only 1 local account on the machine.

The problem is I get as far as having them get to the adapters, right-clicking on the Local Area Connection and selecting properties to get to the TCP/IP settings and UAC pops up saying they need to enter an administrator username and password.

They enter the only account on the computer which definitely has admin privileges (it would have to as the only account anyway) and it tells them that isn't an admin account and they still don't have permissions to view the LAC properties. And of course the same deal if they try to turn UAC off.

Any idea why they are running into this wall and how to solve it??

Give this a shot:
Built-in Administrator Account - Enable or Disable

Thanks for the reply.

I will try that but I don't believe that will get us anywhere because you need administrator privileges in order to access the Local Users and Groups utility and the issue we are having is that the user can't access any functions on their machine that require administrator privileges.

As I feared, no luck. They get an access denied error when attempting to enable the built-in administrator account. We've fallen onto reinstalling the OS as the only option left to us.