Alas, I can't help you with your D:OS problem, but if your save files really got corrupted without any apparent reason, your hard drive may be failing. You should do a S.M.A.R.T. test of the drive. Search the web for "windows 10 smart test" for instructions.
Also, you should backup your existing good save(s) on a different drive immediately if they're that valiable to you. Multiple "normal" saves alongside the quick and auto saves are recommended, if you have the space. I make one at the end of every playing session.
Besides, regular backups of all your important files are highly advisable (there's a saying among the tech-savvy that data without backup isn't important by definition). I would recommend at least two local backup hard drives for rotating backups which you should stash at a secure place. If you encrypt the backups, you can store them at work or with friends, neighbours etc.
