Open Command Prompt as administrator
Type `wmic path softwarelicensingservice get OA3xOriginalProductKey`
Press Enter
Check the displayed key if available
Open PowerShell as administrator
Type `(Get-WmiObject -query ‘select * from SoftwareLicensingService’).OA3xOriginalProductKey`
Press Enter
Check the displayed key if available
Open Registry Editor
Go to `HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionSoftwareProtectionPlatform`
Check `BackupProductKeyDefault`
Use a trusted third-party key viewer tool if needed
Check your Microsoft account digital license if Windows was activated online