Activate Windows 10 when OEM key is missing

In the end, we found that machines that had motherboard servicing were not set up with an OEM key in BIOS/UEFI.

The cards with keys Dell sent were all bad, most likely MS invalidated them. MS confirmed they were bad.

Dell noted that any machines under warranty they would fix, but the rest are not fixable under warranty, and we are reimaging with Linux or a BYOL license.

Here is a helpful command to find if an OEM key is in BIOS/UEFI.

wmic path softwarelicensingservice get OA3xOriginalProductKey

If that returns empty, there is no Dell OEM key, and Windows won't activate.

If there is, it will. We are now auditing our fleet before end-of-warranty.