explorer disappears after IE patch

When users run mandatory Upgrade to IE 5.5, explorer does not come back up. A user put the explorer.exe in startup menu and it worked but user always gets message on startup:

sysbot.exe – Illegal system DLL Relocation

The system DLL user32.dllwas relocated in memory. The application will not run properly. The relocation occurred because the DLL C:\WINNET\system32\USER32.dll occupied an address range reserved for Windows system DLLs.
The vendor suppling the DLL should be contacted for anew DLL.

Does anyone know how we would get rid of this user message?
Thanks,
Joy