Sửa lỗi 'IsThreadDesktopComposited' Firefox 3.5

The procedure entry point IsThreadDesktopComposited could not be located in the dynamic link labrary USER32.dll

I just installed Firefox 3.5 after using 3.0. When I went to open it I got an error message reading
firefox.exe - Entry Point Not Found
The procedure entry point IsThreadDesktopComposited could not be located in the dynamic link library USER32.dll
if I click ok it then opens firefox. So Firefox seams to be working it is just really annoying to have to go through this error every time I want to open firefox.
I have already tried completely uninstalling Firefox including my Firefox profile and then reinstalling it. That did not change anything.
Is there anything else that I can do to fix this problem.
Thanks

Solution:

just found the following info. from other site and it works for me:
If that's the exact error message (...IsThreadDesktopComposited...)
then the most likely cause is that some program has erroneously installed files intended for Windows Vista only under WinXP.
Go to your "C:\Windows\System32" dir
Look for this file:
DWMAPI.DLL
If it's there, either rename it to DWMAPI.DLL.OFF or move it out of the Windows dir to some backup folder elsewhere (don't delete it just yet, just incase).
DWMAPI.DLL shouldn't even exist on WinXP, as it's part of Vista's Desktop Windows Manager.
Now see if you get that error message when opening Winamp and other programs.
If it's not even there, or if the error still occurs,
then it means some other WinXP system file(s) have been wrongly replaced with the Vista version...
and you'll need to use Dependency Walker to try work out what files need restoring.