Interesting read.
I've also encountered one of these particular scams. The victim was one of our clients.
These scammers ran through similar processes to gain remote access to our customer's PC. Their English was broken, and they had informed that they were a Microsoft certified company. They used a few sly methods to convincingly prove their point. Fortunately he also smelt a rat and gave us a call to explain the situation.
I'd not experienced an attack like this in the past so this was new to me too. We explained that this was a fraudulent attempt at repairing the PC, and informed that they should turn the PC and internet off immediately and end the call.
I then remoted onto the customer's PC to see the damage. I found that the scammers had used GoToAssist to gain remote access to the PC, and I also found files that appeared to be malware in the Downloads folder.
Fortunately the customer had ended the remote session and call before the scammers could install any malicious software or do any real damage. I ran multiple malware scans and fortunately found nothing. I looked at MSCONFIG, HiJackThis, checked the services, installed applications, and all of the other usual checks. I also checked the integrity of the customer's data, however everything seemed to be intact and our customer appeared to have had a lucky escape.
The number that was used to call our customer originated from India, and a quick search of the number found
this.
These people somehow convince the vulnerable, uninformed user that they are Microsoft certified, or a part of Microsoft. They use a professional method of gaining remote access, and then charge ludicrous amounts of money to "repair" their PC.
Our customer was informed of such dangers, and how they could possibly originate. We informed that they should keep a close eye on their emails for potential spam, fraudulent phone calls like the one experienced, to change their passwords and keep an eye on their personal information for possible modification or hacking attempts.
I fail to understand the logic of this. For all of the effort these guys put into doing this sort of thing, they could set up a legitimate business and run it properly. However the lengths these guys will go to will never cease to amaze me.