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Am I allowed to transfer my software from one device to another when I upgrade using Windows Anytime Upgrade?
Microsoft is modifying the end user license agreement for full packaged product versions of Windows Vista purchased through a retailer or from Microsoft, and then upgraded using Windows Anytime Upgrade. Under the terms of the modified license agreement, you are now granted the right to uninstall Windows Vista and then reinstall the operating system on a different computer. Provided you uninstall the operating system from your original computing device and do not share the license among multiple devices, you are no longer limited in the number of times that you may reassign the license to different devices. This modification is effective immediately, and will be included within future versions of the end user license agreement. All other terms of the end user license agreement apply to your use of the software.