I have Windows 7 x64 installed with Kaspersky's v220.127.116.115 Beta Antivirus (with Firewall) For Windows Workstations, call it "K" for short, set to its defaults. When K installed, it disabled the Windows firewall as I expected. I can reach the internet with Internet Explorer when I boot Windows Vista 32 but not with IE x86 in Windows 7 x64. I tried disabling K, but IE was still broken. Out of curiousity, I tried installing Firefox v3.06 x86 in Windows 7 with K active and it worked instantly. I downloaded the following Microsoft updates and installed them just before the problem started: KB962921, KB963660, KB967355, and KB967540. It might be worth a try to uninstall these updates one at a time and see if the problem vanishes. If it doesn't, is there any way short of a repair install to fix the problem? I was going to do one, and thought I had completely disabled and exited K before starting Windows 7 setup, but a long narrow white rectangle with length about the size of all the icons in the task tray appeared with three announcements to the effect that "this port or that application had been blocked or allowed by default." So I bailed out. Apparently I missed disabling one of K's multiple security programs. I clicked on help to investigate further, but it's in Russian. That doesn't change the fact that it was nice of Kaspersky to offer free beta security software for use with Windows 7 Beta.