Well Apparently the boot-time scan found a worm virus, I tried to delete it by telling avast to do it, and about after the 8th try it actually worked, but the whole scan ended with it
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. So now I had to start the scan again.
Honestly sometimes you don't even think your computer has a virus, but they still lurk around in the background, some even take snapshots of your work and send it back to the hacker, sneaky little things. And 1 scan is definitely not enough if you find several viruses after a full scan. Worms are self replicating and spread very fast, also very hard to catch by virus scanners.
I'm considering doing a format. It's the best way to entirely clean out a system. MSE isn't the best, but it's alright, it's sort of like windows defender with real-time security.
btw to the OP, what OS are you using on the infected computer?