Update: I'm working on creating a bootable Windows 10 USB drive. My only other computer that I have access to is a Macbook, so it hasn't been as easy as it would be on a PC.
In the meantime -- after leaving my computer powered on at the login screen for an extended period of time (a few hours or longer), when attempting to login, my login name is shown on the screen but without a password entry field. I waited a while longer, and eventually the password field showed up, and I was able to log in. Logging in took a long time (+5 minutes), which is really unusual for my computer (usually, it's lightning fast). After finally logging in, I tried to open MBAR, explorer.exe crashed, and I had no choice but to hard reboot my computer. Anyway, I'm starting to suspect that this locked-out-of-login-screen fiasco may be the work of another extra-crafty piece of malware, and not a bug as I'd initially thought. Could be wrong, though. I'm no expert.
What should I do once I've got my Windows 10 USB at the ready?
Edited by brendyman, 14 May 2017 - 09:45 PM.