Booting hangs at the screen with the revolving dots progress animation.
My machine has two hard disks in it. One is loaded with Win 10, recently upgraded automatically from Win 7 Pro. The other disk i recently installed Win 7 Pro on. Both were working okay until last week when i logged on and got a message that my E:\ drive (the one with Win 10) needed to have CHKDSK run on it. CHKDSK ran and it's last action before quitting was to go through every single security ID file and replace it with "default security ID" files. Over 700,000 files. It took over 8 hours to complete this process. After that I could no longer boot into the disk that ran Win 10. I also couldn't access that disk from my other hard drive (the one running Win 7) even after repeatedly changing security permissions by entering the disk properties preferences menu. I ran a virus check using Avast Antivirus. It found several medium-level threats and repaired them. However, that disk still remains inaccessible to me with any program or while booting up. I've tried using the BIOS setup menu to change the order of drive booting, and even disconnected the other drive. No luck there.
At first i was sure it was a system problem, but now i'm starting to believe it might be a virus.
I would appreciate any assistance. Thanks very much.
My machine is a custom-built running on dual AMD64X processors 3.4 Mhz with 4 Gb of RAM. Video card is NVidia 750Ti with 1 Gb memory.