Windows 7 "Incompatible" Driver Blocking  

For your networking driver, go here: Marvell: Support and select Win 7 64 bit and your model number from the drop down list (sorry I cant get you any closer without giving you a direct link, to the download which is against Forum Policy)


I cant find your particular wireless model, Dell might have it on their site local to you though.

It will be a Vista driver regardless, so will need to be installed as per the tutorial I posted above

Good stuff Hopefully SFC will sort you USB issue. If not it might have to be a Repair Install

ok so that confirms the suspicion that its a Corrupted System file or driver, In that Case I recommend you do a Repair Install to fix the issue. It won't delete your personal files, or installed programs, it will just "Repair" Windows

I wonder.... have you installed any updated Drivers from Windows Update? or do you leave your machine connected to the internet while Installing?

Just a shot in the dark here, I could be dead wrong, but its possible the drivers it has pulled from Windows Update are incompatible. Windows will try to pull updated Drivers from Windows Update while installing if

It might be worth reinstalling, and disconnecting from the internet while doing so. then hide any driver updates that Windows Update offers you. I have had this issue with my network drivers, and keyboard drivers. The Drivers offered from Windows Update actually broke it.

I find it odd that it was working, and now it isn't Thats the only explanation I can think of.