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In simple terms, the SSD works fine when plugged directly into a computer’s M.2 slot, but HLK testing is stricter and sometimes doesn’t see it if the setup isn’t exactly right. The usual reasons are that the server BIOS doesn’t have NVMe enabled, the SSD driver isn’t WHQL‑signed, or the storage controller is hiding the drive behind RAID or virtualization. The fix is to make sure the BIOS and firmware are updated, the Microsoft NVMe driver or a signed vendor driver is installed, and the HLK client is set up to give the test system direct access to the SSD. Checking the HLK logs will confirm if it’s a driver or configuration issue. If all of that is correct and it still doesn’t show up, it’s usually a driver signing mismatch that needs to be aligned with Microsoft’s HLK requirements.
You can find the setup details in the official article here for the exact steps: https://learn.microsoft.com/en-us/windows-hardware/test/hlk/