I downloaded a Windows update last night ( as a novice - just because Windows prompted me as I shut down !!) :
I am now getting the following message when I start up :
The system DLL user32.dll was relocated in memory. The application will not run properly. The relocation occurred becuse the DLLC:\WINDOWS\system 32\HHCTRL.OCX occupied an address range reserved for Windows DLLs. The vendor supplying the DLL should be contacted for a new DLL.
sorry i cant remember the link i got it from but theres a patch available, i had the same problem and downloaded a patch from microsoft's site and its fixed now.