I wanted to update my drivers because I was trying to play a game and it mentioned that my drivers weren't up-to-date. So I went to the official nvidia website and downloaded the latest drivers: 301.42-desktop-win7-winvista-64bit-english-whql and tried to install them. Whenever I try this it get's stuck at the graphics drivers and says NVIDIA installer failed.
Did you uninstall previous drivers - or just remove them? - i have tried to install new drivers on top of old - it did not work - but then i uninstalled old drivers - and restarted and installed new - that worked..
Try renaming the folder "C:\Program Files\NVIDIA Corporation" , i tried many ways, deleting registry entries, system restore, traditional uninstall, compatibility mode, etc. but nothing worked, only when i got renamed that folder VOILA! it worked. (That worked for me).