How do I get a Windows authentication code for a PC that cannot upgrade from Windows 10 to Windows 11?

Dear @tj nam,

Thank you for posting your question in the Microsoft Q&A forum.

We apologize for any inconvenience you may encounter when using our services/ products. Based on your description:

Windows authentication code is a product key or digital license

• A product key is a 25-character code (XXXXX-XXXXX-XXXXX-XXXXX-XXXXX) used for activation.
• A digital license is tied to your Microsoft account and does not require entering a key manually.

Kindly try these following steps:

Use PowerShell to retrieve the product key

Run PowerShell (Run as Administrator) > type:

slmgr /dlv

You will see activation status and whether it is using a digital license or a product key.

To get a product key, run:

(Get-CimInstance -Query 'select * from SoftwareLicensingService').OA3xOriginalProductKey

If blank, your PC uses a digital license tied to your Microsoft account or enterprise activation.

Note: A digital license is activated and linked to your Microsoft account. You do not need a product key.

Refer to this article to find your Windows authentication code (product key): Find your Windows product key - Microsoft Support

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