iPhone Device is not specified in Windows 7 after update to iOS 5

After i updated my iPhone to iOS 5, my iPhone device become unspecified. However, my iTunes still able to detect my iPhone and sync with no problem.

Another thing is my iPhone icon disappear and become a weird device, and it shows Apple iPhone instead of my phone's name.

I have tried:

1) Completely uninstall and reinstall iTunes and relevant apple software by following below step

http://support.apple.com/kb/TS1538

2) Restart PC

3) Restart my iPhone

4) Hard reset my iPhone

None can solve my problem, please help!