And this is why you should never use the Windows default locations in your user profile for Documents, Videos, Pictures, Music, etc., if the OS goes south and you have to reinstall it on a clean drive, you lose everything. Every Windows system should have at least a C: drive and a D: drive, C: for the OS and all the other stuff Windows and installation routines insist on putting in your user profile despite what you may tell them about where to install things, and D: for everything else. As a minimum, I set up my systems that way, install only Windows on C:, all application software is installed in D:\Apps, and all my personal files go into D:\Personal. And if you have more than one drive, even better, set that up as E: and put all your documents, pictures, etc. on that one.
First rule: keep the system, the applications, and the users, isolated from each other. Windows doesn't really let you do that, some programs don't offer the option about where to install them and will go into C:\Program Files or C:\Programs or something similar, depending on what version of Windows you're using, and there'll always be something that ends up in your or the system default user profile, but with a little care and attention you can do about 80% of it. Second rule: never accept defaults inconsistent with the first rule, keep control as much as you can over where things go.
