There are special programs that are designed to backup the main drive in case its software crashes because of a virus etc. And I agree that they should be used if one can be obtained. They usuaully run a few bucks. Some might be available for free on the Internet. I haven't checked.

Often times just one or a few Windows files will get destroyed. And then just copying a large number of files back from some other drive will fix things.

People who are highly dependent on their computers for work or even just socializing need to get those backup procedures developed BEFORE they are needed. Once drive problems are encountered it can be impossible to fix things and lot of time and effort can be lost. And as stated before, it can be a good idea to do any experiment work on a backup computer. I have been testing this one popular social computer program lately. And it appears that when it installs itself it also brings along a flock of unwanted additional programs that then create pop up adds etc. It and they are probably going to get dumped by going back to a Restore Point from before they were installed.

If a drive encounters problems repeatedly and has to be fixed then it might be a sign of more serious problems that need to be addressed such as a major virus infection or some system component such as the drive itself that is failing.

These are personal opinions.