However, there are two ways to do this.
The first is via the Services menu.
Start / Administrative Tools / Computer Management / Services and Applications / Services / AD FS 2.0 Windows Service
(Description : This enables Active Directory Federation Services 2.0 to issue security tokens and information cards.)
The second is via the command line. Ensure you are running as Administrator.
C:\Windows\system32>net stop adfssrv
The AD FS 2.0 Windows Service service is stopping.
The AD FS 2.0 Windows Service service was stopped successfully.
C:\Windows\system32>net start adfssrv
The AD FS 2.0 Windows Service service is starting........
The AD FS 2.0 Windows Service service was started successfully.
Sure beats stopping / restarting the whole Windows 2008 server!