A recent hardware or software change might be the cause. What I cannot do: I cannot boot into Windows - I get this message: Windows failed to start. Although automated Windows repair fails, I can get to command prompt when I boot Windows install from USB drive, and I can see my drive and all my data. What I can do: I can boot Windows install from the USB drive, and I can boot the Hiren's Boot CD.
NVIDIA drivers upgrade crashed my Windows 7 installation, so I'm working to undo the damage.
