I'm not sure if this is a virus or not, but I don't know what to do. I'm assuming I got it from a bad torrent I was downloading. I use Avira antivirus and it's always worked perfectly, but since yesterday windows defender (which I've never used and has never done anything since I've had my comp) keeps popping up every 20 min or so saying one of 3 things. It either says it found a trojan and I need to activate defender to protect myself. It says I have a spambot on my comp and lists the contacts of mine its been sent to (none of which are contacts of mine, most don't even look like real emails). or it says an illegal connection is trying to be made and i need to stop it. Whenever I click out of one of these pop ups another window pops up saying i need to pay to upgrade windows defender to premium version. I'm pretty sure this is some sort of virus, but when I ran a full system scan with Avira it didn't find anything. And when I go to uninstall defender it's not on the list of programs I can uninstall. What should I do?

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