Following its decision earlier this month to drop Vista's "kill switch," which puts Vista in reduced functionality mode if the license key fails to validate with the WGA system, Microsoft will also tweak its product activation and anti-counterfeit technology in XP with the release of Service Pack 3.

According to the company, new installations of Windows XP SP3 will give users the same optional 30-day grace period currently offered to Windows Vista customers instead of requiring the activation key during the installation process itself. After the 30-day grace period expires, users will have to enter a valid product key and activate the system before they can log on. As with previous service packs, no product key will be requested or required to existing Windows XP installations being upgraded to SP3.