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# When the activation grace period (or evaluation trial period) is almost expired or ended, log on to Windows 7 desktop, and open a Command Prompt window (i.e. type Cmd in Start Search and hit Enter).
# Type any of the following commands into the command prompt, and then hit Enter: sysprep /generalize
slmgr.vbs –rearm
rundll32 slc.dll,SLReArmWindows
slmgr /rearm