Following along with what Mike said, since you have a desktop computer
MAKE CERTAIN THAT YOU HAVE ANY OTHER INTERNAL HARD DRIVES DISCONNECTED FROM THE MOTHERBOARD (VIA SCSI, SATA, eSATA PORTS) AND ANY AND ALL USB DEVICES EXTERNAL TO YOUR PC AS WELL SUCH AS PRINTERS, WEBCAMS, WACOM TABLETS, PRINTERS, SCANNERS, ETC. This is how computer Techs typically fix a broken Windows anything PC. When you take it into the repair shop, the Tech doesn't have to worry about all the extra external junk you have connected to it; they only have to fix what's inside the Case. So, the first thing they do is to crack open the case and see if you have additional secondary drives, setup in normal mode, RAID mirroring mode, etc. Or if you have a PCI SCSI or RAID controller card plugged into your PCI bus; that all needs to get ripped out in most cases unless the Tech is very familiar with the PCI storage card you have and he knows how to get your Windows reinstalled without ripping that out cause he's done it before.
Home users are typically not aware of this constraint, so they leave all their extra drives and usb devices hooked up, and as soon as they get it repaired, wham!!
A new AU update comes in and kills windows because of 1 or more of those devices get their drivers scrambled from the update. That's now happening about every 2 weeks with the latest AU pushes. We've now had like 8 of them since Aug. 2nd.
If you have no other secondary drives inside or outside the computer connected, you can then and only then proceed with the above suggested repairs!
The only way this would be different is if you have a Tech come out to your home such as a Best Buy Geek Squad agent and then they pretty much have to disconnect all the stuff we are talking about, then crack open the case and see what hidden storage goodies you have inside the box and then disconnect all of those before proceeding with the in-home repair attempt.
Best of luck with the repair.
Post back if you get stuck or have any further questions. We are here 24x7x365.
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