Back when Windows 7 came out, I shelled out the ~$700 to convert all the computers in my house to Windows 7. Ever since then I've had a friend considering buying Windows 7.
He recently took the plunge an invested in a copy of Ultimate (64-bit). I backed up his personal data, formatted and Installed a clean copy of Windows 7. On first boot I ran Windows Update (his hardware was all supported by Windows) and did the required restart. During the restart, the computer Blue-Screened, restarts automatically, entered startup repair the second time, "fixes it", and the cycle starts again.
So I figure "Okay, one of the updates is bad." I reformat and reinstall again, and the computer first-boots normally again. Just to test I restart the computer and the bsod/repair cycle starts again.
I finally gave up for the time being and just reinstall Vista 64-bit on their again and it works fine. His is the only computer I've had this happen to, and I've installed 7 on about 12 other computers so far. (No, I did not miss the irony) Does anybody have any suggestions?