File History (windows 10) Acting Up Again.

Hi, me again;

I'd previously had an issue with File History after plugging in the wrong external hard drive (thanks for the quick help on that one, by the way), but now it seems to have developed another issue unprompted.

As of the last few days, the File History window just says "Your data is not yet backed up" (it is). I've had this happen a few times in the past, and usually if I just disconnect/ reconnect the hard drive, close and reopen the File History Window or just try clicking the 'Back up now' button a few times it will eventually start working, but unfortunately none of those seem to be doing the trick this time.

When I click 'Back up now' the button just goes grey, the system seems to have a good long think about it, then... nothing.

I've already tried clearing out everything in the FileHistory Configuration folder (as was advised in my previous topic) and oddly if I try to turn off File History it just... doesn't seem to work? It doesn't actually turn off. Is there anything else I can try?