WinCC - older version or not fully installed?

Hello,

          I have installed Simatic S7 5.6 and WinCC Flexible 2008 Runtime SP5 on a Windows 7 computer.  Running Simatic Manager brings up the error message

'Simatic WinCC flexible  -  Older version or not fully installed'

           as far as I know, WinCC 2008 is compatible with S7 5.6 and I have installed both fully.  Does anyone have any ideas on how to get this running?

Thanks,

Rath