Last year, Microsoft said users can downgrade the buy of new computers installed Windows Professional to Windows XP Professional 7 older in a limited time: 18 months after introducing Windows 7 or when Microsoft released Windows 7 SP1. Nearly 2 months ago Microsoft admits working on Windows 7 SP1. However, they have not declared launch schedule. Then the only option for those users who do not participate the Software Assurance is deploying Windows XP using Windows XP Mode.

SA is the upgrade program to make sure Microsoft's payment of annual fees. The company registrations for this program or buy Windows through licensing programs have large downgrade from any version of Windows to any earlier version of Windows.
Microsoft said will permit the reduce to Windows XP after 18 months have passed, or until they launch Windows 7 SP1. After Microsoft launched Windows 7 SP1, users can only reduce Windows Vista Business.