I am a network administrator at a law firm in Toronto. One of our lawyers mistakenly clicked on an ad site that was controlled by these guys. When the attack starts a browser popup appears with their phone number and a warning that your computer is locked with a virus. Call Microsoft. When you call the phone number provided they ask you to press the start button on your keyboard and run a program. Once the program runs they give you a code to disable the lock on your computer. This is red flag #1, they knew the code to unlock the virus. Clearly it was their virus to begin with. Then they go through your computer, clean up the registry and install malwarebytes as well as their support tool. From now on their phone number will show up on your toolbar. For this nice service you have to pay upwards of $300.00 for this service guy to "fix" a problem that they created.