last night i got a call from man claiming to be with windows service center claiming my computer had been hacked they took control of computer to clean it up, and charged me 299 dollars for service, and put webroot security icon on desk top along with a defrag and cc cleaner icon, i gave them payment with my visa credit card, guess maybe i should call visa and stop payment ? they did claim they would call back this morning to make sure my computer is working, they also seemed to little upset when they asked for payment with a check, which i refused to do, but did pay with visa cc, i guess any suggestions would help, thanks