My story isn't literally "Turning it off and back on" but pretty similar. So I do web hosting support, and a customer was having an issue with a WordPress site, his themes weren't working, everything looked like it had no CSS for it, and half the site functions weren't working. So I took a backup of the server before I started working on anything incase I fucked anything up. I tried quite a few things and nothing I could do could get it to work, none of the normal wordpress tricks did the job. And after a while I noticed something... the database had nothing in it, it looked just like a new wordpress install, meaning I likely accidentally overwrote the database, and all of the sites content was gone. So I restored the orriginal backup I had, since I screwed everything up past the point of repair, and on a whim reloaded the site, which wouldn't have been something I would have normally done because with all logic, it should have been broken; but the site was fixed. I still don't know what actually caused it to break, it was probably a file permissions thing, but for some reason restoring the backup worked.