The Talos security blog, sponsored by Cisco systems, highlights an increase in fake telephone calls, emails, and website popups that pretend to aid end users in identifying a virus or other system problem.  Often a scammer with an untraceable telephone number will work with user and convince them to share credit card numbers or allow them to plant “diagnostic” software on their system.  Users should be aware that Microsoft or other companies will not contact users by phone or email in this manner.   

http://blog.talosintel.com/2015/11/tech-support-scammers.html

The amount of fraudulent actors masquerading as legitimate tech support has been on the rise since 2008. According to David Finn, executive director at the Microsoft Cybercrime Center, tech support scammers have made nearly $1.5 billion off of 3.3 million unwitting victims just this year. These scammers typically convince the victim into allowing them access to his/her computer through remote control applications such as TeamViewer. They then present benign processes as malicious, or at times even spread malware themselves. Afterwards, they charge hundreds of dollars for the service.

There are several avenues through which these scammers reach their victims. One of the most insidious are pop-ups and websites asserting that the user’s computer is riddled with viruses, and that the only way to fix the problem is to call a provided tech support number.