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Your version of Windows 7 Ultimate should have the Windows Anytime Upgrade facility providing it is a retail copy.
Click Start>All Programs>Windows Anytime Upgrade then type in the Windows 7 Ultimate product key and wait while the upgrade completes - typically half-an-hour or so.
You'll probably need to use the automated telephone activation wizard, Start then type slui.exe 4
and follow the instructions.
If your copy of Windows 7 Ultimate doesn't have Windows Anytime Upgrade you need to log onto the Microsoft store and purchase an upgrade product key there. As soon as your credit card payment has been accepted, a product key will be e-mailed to you. http://windows.microsoft.com/en-GB/w...nytime-upgrade