After rebooting my computer there is a message that states:

Your Windows product must be activated within _ days.
Do you want to activate Windows now?

After I click yes getting a Windows Product Activation window appears.
Windows is already activated. Click OK to exit

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Deactivate your machine and then reactivate it.

Go to Start > Run, and type:

%systemroot%\system32\oobe\msoobe.exe /a

If that doesn't work, then run regedit, navigate to:

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\wpaevents

and change any single number in OOBEtimer in the right pane. Close regedit and try the command in the Run box again.