I had a developer trying to connect to the admin panel of IIS7. They could open the MMC just fine, but when they clicked on the server (local server) it would give a failure:

There was an error connecting. Do you want to specify different credentials?

And then it would fail again.

Open a command prompt on the server:
%windir%\system32\inetsrv\appcmd list sites

So I edited the redirection.config file given, and found that one of the developers had put
Changed it to false, and yay it works! Oh, I had to close IIS Admin and reopen.