How To Fix Windows 7 Activation Status Not Available |top| Link

: You can reset the activation timer and licensing status by running slmgr /rearm in an elevated Command Prompt. If this fails with an error, you may need to navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SoftwareProtectionPlatform in the Registry Editor and change the SkipRearm value to 1 before trying the command again.

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