Windows 10 Home Upgrade to Pro using OEM key

1. Switch to offline mode
2. While offline, use the default Windows 10 Pro key to perform an upgrade to Windows 10 Pro
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3. After upgrading, go online again
4. Click Start > Settings > Update & security > Activation > to change the product key.
5. Enter your Windows 10 Pro OEM product key, click OK and activate Windows.

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