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Lost OEM activation key on preinstalled PC

Anton Berggren 20 Reputation points
2026-04-02T13:24:26.56+00:00

Setup 3 signage screens with 3 SDM PC's. (AMI BIOS) (Advantech DS200)
Came with Windows 11 Pro preinstalled.
Three paper/carton sleeves with CD and peelable activation key which we scratched to reveal them.
Activated all three pre-installed windows with those keys successfully.
Using local admin account on all three pc's.

The issue now is that the key is not stored in the bios on the SDM pc.
We accidentally throw one activation sleeve away so the activation key are gone :(
Cant reinstall windows. We have the other two sleeves at our hands so them pcs can be reinstalled if they are needed to.

I can only see the last 5 characters on the installed activation key in windows.
can microsoft help me and retrieve the key from the results i got from "slmgr /dlv" ?

There is activation ID and other information.

Windows for business | Windows Client for IT Pros | Devices and deployment | Licensing and activation
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  1. Jason Nguyen Tran 17,675 Reputation points Independent Advisor
    2026-04-02T14:21:16.3266667+00:00

    Hi Anton Berggren,

    Unfortunately, Microsoft cannot retrieve the full OEM product key from the system once it has been activated. The reason is that Windows only stores a partial view of the key (the last 5 characters) for security purposes, and tools like slmgr /dlv or wmic path softwarelicensingservice get OA3xOriginalProductKey will not reveal the full OEM key if it was manually entered from a sleeve.

    On devices where the OEM key is embedded in the BIOS/UEFI, Windows can automatically detect and use it during reinstall. However, in your case, since the SDM PCs do not store the key in firmware, the sleeve is the only source of that license. Without the sleeve, there is no supported way to recover the full key from the system.

    The best path forward is to contact the hardware vendor (Advantech) with proof of purchase. They may be able to provide a replacement key or guidance on how to reinstall Windows on that unit. Alternatively, you can use one of the remaining two sleeves for reinstalling the other PCs, but for the lost key, vendor support is necessary.

    In short, the missing sleeve means the key cannot be retrieved from Windows itself, and vendor assistance is the recommended solution.

    I hope the response provided some helpful insight. If it addressed your issue, please consider marking it as Accept Answer so others facing the same problem can easily find the solution. If you need any further assistance, feel free to leave a comment.

    Jason.

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  1. Q&A Assist
    2026-04-02T13:24:47.1966667+00:00
    AI generated content. This question contains an answer created with AI from Q&A Assist. Learn more

    The full OEM product key cannot be recovered from slmgr /dlv output or from the last 5 characters shown in Windows. slmgr only exposes partial information and generic installation keys; it does not provide the full unique key that was on the discarded sleeve.

    For OEM systems, activation is normally either:

    • Embedded in firmware/BIOS (OEM key in UEFI), or
    • Performed using the unique retail-style key on the COA/sleeve.

    In this case, since the SDM PCs do not have the key in BIOS and the sleeve for one device is lost, there is no supported way for Microsoft to reconstruct that specific key from slmgr /dlv data alone.

    Available options based on the documented guidance:

    1. Confirm whether a valid license is still present
      If Windows is currently activated on that device, it has a valid license associated with the hardware. If a major hardware change occurs or Windows is reinstalled incorrectly, activation may fail with errors such as 0x800704CF, 0xC004F211, 0xC004F213, or 0xC004F212. In those cases, the documented remedies are:
      • Use Start > Settings > System (or Update & Security) > Activation > Troubleshoot and follow the reactivation path, including the “reactivate after a hardware change” option where applicable.
      • If the wrong edition is installed, the troubleshooter may detect a digital license for another edition and guide installing the correct edition.
    2. If Windows reports no valid product key or license
      When Windows cannot find a valid license (for example, error 0x800704CF or similar), the official guidance is:
      • Use a valid product key from packaging/COA or purchase a new license:
        Start > Settings > System (or Update & Security) > Activation > Go to Microsoft Store and buy a genuine Windows license, or select Change product key and enter a 25‑character key from another valid source.
    3. If the original key media is lost
      Documentation for lost keys and activation issues indicates:
      • If the key was on physical media (card/sleeve/COA) and is lost, the supported path is to contact the device manufacturer or the reseller that supplied Windows, explain that the preinstalled key media was discarded, and request assistance or replacement.
      • If they cannot provide a replacement, a new retail license must be purchased.
    4. If activation later fails after hardware changes
      If these signage PCs ever need hardware replacement (for example, motherboard) and activation fails with 0xC004F211/0xC004F213, the documented options are:
      • Run the Activation troubleshooter and use the “reactivate after a hardware change” flow if available.
      • If that fails and no product key is available, a new license is required.

    There is no supported mechanism in the provided documentation for Microsoft to regenerate or disclose the full OEM key from slmgr /dlv output or from the last 5 characters alone. Recovery must come from the original physical key media, the OEM/reseller, or by purchasing a new license.

    References:

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