While surfing the internet, a warning popped up on the screen indicating that the computer was infected with a virus/malware and that you should contact this company immediately to have it removed. Upon calling the company, they identified them a being from "Microsoft" and convinced the user to provide remote access to their computer. At this point, the "technician" Patrick Rodgers proceeded to install some "software" and perhaps download the entire contents of the computers hard drive under the guise of helping to fix it.The next day, the victim contacted me (a software engineer) and I advised him to immediately disconnect his computer from the internet (to cutoff their access to it). A short while later, I scanned the computer using the latest Kaspersky security software and it uncovered hundreds of Trojan programs designed to provide hackers access to the computer and to monitor their keystroke inputs (allows passwords and logins to be stolen). They had charged this person $300 for the "service" to supposedly clean the system and tried to sell them another security program for $300 more. Turns out this security program sells for less than $100 everywhere else. We immediately stopped payment on the charge and got a new credit card number.Fortunately I was able to restore the system to an earlier backup/image and rescanned to confirm no traces remained. Unfortunately, going back to a known good backup or re-installing the operating system/programs from scratch is the only sure way to know what the scammers installed is truly gone and the system is secure again. We cutoff all contact with the company and never heard from them again.