When I open Safari a web site appears saying I have a virus
The message is as follows:
System has Detected Security Error, Due to Suspicious Activity and Network Firewall seems to be Turned Off. System Might be infected with Trojan BackDoor.Flashback. Please Contact Support - Certified Live Technicians For Help 1(844) 291 9491 and a website http://www.rremail.in/
I cannot move off this site or use safari. I can write this question by using google Chrome. How can I clear this off my computer?
iMac (27-inch Mid 2011), Mac OS X (10.7.5)