In the mask of Free Anti virus Hackers are attacking the valuable sites and by spreading vulnerable bugs in to those sites. Staling valubale information form those sites.
Hackers are playing a trick by sending a link that your Free anti virus software has been expired so please click here for life time update or for extesion of one year or available @very chaep rates.
Don't get exited by this offers, if you've done this then your PC will be damaged and your valuable content will be tranferred to the Hacker.
A special advice is BUY ORIGINAL Antivirus softwares from any authorised dealer in your area to protect your PC and your valuable content.