Hubby and I had an issue with this yesterday. Hubby is currently playing Dark Souls 3. He was in the game with his Steam Browser open. He clicked on a link and BAM! He had a drive-by or ransomware virus. Being that he is very computer savvy he was able to fix the situation. He just fixed his mom's computer who also had a ransomware virus. Hubby definitely did not do anything stupid, it just happened. All it took was one click.
How you might have gotten it is in one of these links. The other is a removal technique. You don't need to download anything that will cost you. If you want one that has a 30 day free trial and you use that...Hitman Pro. HitmanPro 3 - SurfRight
How? Visiting the wrong sites, clicking on dangerous or unknown links, opening links in email, getting sucked in by dubious "friends" on Facebook and Twitter.
It helps to educate yourself about ransomware and to use adequate protection. (Don't surf the Net without an appropriate condom.)
Above all, back up your hard drive (and your cloud) and keep the backups away from your computer, so that when you get hijacked you'll have some options.
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