Hello, For infos, just avoid installing KIS 2013 version 22.214.171.12490 available in final version on Kaspersky site, on a Windows 8 system. After installation, I could not launch Firefox version 15 only IE10 and many others problems. Then I tried to unistall it but the process stopped near the end and blocked all the system. Finally I launched a restoration to a restore point, I created just after activation of the OS. Everything is ok now However KIS2013 works perfectly on Windows 7. Good Luck for those who have already tested KIS2013. Regards.