Your system works fine, but it complains loudly about foreign software. Makes its presence known, but doesn't do anything. Secretly, you wish it would.
Files disappear, only to reappear mysteriously a year later, in another directory.
You know it's guilty of trashing your system, but you just can't prove it. Every three minutes it tells you what great service you're getting. This revolutionary virus does not horse around. Won't allow you to delete a file, regardless of how young it is. If you attempt to erase a file, it requires you to see a counselor about possible alternatives.