I have been getting unsolicited pop ups advising me that I have viruses that must be cleaned immediately if I want to avoid a crash. They are from a Microsoft Secuity Essentials Alert. As I do not have Microsoft Security Essentials, how would they know what viruses I have, and why would these viruses not be picked up by McAfee? May be just a way to get me to purchase Microsoft Security Essentials, but if so is a slimmy approach. Has anyone else encountered this issue?
Sounds like a fake antimalware issue: http://www.bleepingcomputer.com/virus-removal/remove-fake-microsoft-security-essentials-alert
No antivirus catches most of this sort of thing because of the way it acts which requires some human intervention at some stage in order to activate it.