Yeah, back in my early pirate years as a teen, I downloaded a virus. I was able to sniff it out, and I deleted it. But after every restart the files came back. I eventually found that it had created a separate file that would run a script to check for the existence of the others, and replace them if they were ever removed. I tried to delete this file, and couldn’t; their safety measure was to have that file always be referenced by something so it was impossible to delete. File locksmith was what made it possible to remove, and tattled on what program (yet another part of the virus) was keeping it open.