If you have a bit of spare time, and are in need of a victim to piss-fart around, such stupid "computer fixers" are fair game.
I have developed a few strategies to turn the table on them. One of the favourite is of course, to play dumb. I pretended that I am not sure if I am using an Apple or a Microsoft Windows based system. So I asked them to described, in "great" details, what colour, and what and where I should be seeing such error messages they claimed were stuffing up my computer. Then i pretended that I lost my glasses that I couldn't see very well, and asked him to repeat many times. Then finally, I told him that I didn't even turn the computer on as I didn't know how to. So I asked him to start all over again

The last one was the best as I played the sympathetic card. I told him that I knew it was all a con, but I understand why he was doing that. I told him that I own a large business employing hundreds of people of all racial heritages. I offered him a job with a very good starting salary he couldn't refuse. Guess what? He took the bait and gave me his phone number

Then I asked him to wait for a call from my Human Resource manager within the next couple of days. I think he may still be waiting...