For some reason, the Registry of my computer got corrupted, and I could only boot in "Safe Mode". No matter what I did, even restoring a backup of the boot file, no luck. I decided ro reload the system. I keep all my data on two separate other hard drives, 2 Terabytes each. I got Windows 7 loaded again, everything went smoothly, but I noticed the computer would not recognize the hard drives. I went to the disc manager, and both were there. The common thing to do is to rename them, usually I use the same letter, which I did again, this is not the first time I have done this. Be aware, Microsoft, in one of it's updates, decided if you rename a hard drive, without telling you, it does a quick format, it happens in the blink of an eye, no way to stop it, no other choices given. I didn't find a supposed work around till after. If I had unplugged the hard drives, this may not have happened, but there's no way to know as I would have to have plugged them back in eventually. I have lost every model I have $1000's of dollars of programs, some which I can reinstall, but other I can't, because they were part of a network, and it is no longer allowing activation, even if you had it running. (Yes, Adobe sucks). So, I have to start over. I have spent 48 hours going through the main hard drive taking every file I can take and will have to manually see what they are. I lost everything. Thank You Micro$soft. (and you Apple users, I've seen the same thing happen for different reasons).