This trick should work regardless of where you got your copy of Windows 7 from.

Checking the system properties again shows that I now have 30 days left to activate.

Extend the Windows 7 Trial from 30 to 120 Days

Windows 7 System Properties Activation

Windows 7 Command Prompt as Administrator

Windows 7 slmgr rearm

Windows 7 slmgr Success

Windows 7 Activation 30 days

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