Apple has announced that it will be dropping support for 1st Generation Apple TVs, Windows XP and Windows Vista. They stated it’s because of new security updates that will prevent some features of the iTunes Store. In May, XP and Vista users will no longer be able to make iTunes purchases and owners of the 1st Generation Apple TVs will not be able to access the store at all.
Apple has not released which security changes will affect the devices.
If you’re using iTunes on an older computer, you may want to consider upgrading to Windows 7 or newer to avoid loss of features with iTunes.