NVME SSD disappears from BIOS during Windows operation, but never on BIOS load

Question

I have an SSD (ADATA SX6000LNP) which contains a full-disk C: partition for Windows 10 and is installed in an NVME slot on the motherboard (ASRock X370 Pro4 with P6.30 UEFI). I also have an old HDD as a full-disk E: partition, and no other disk drives. Volume usage on the SSD has never went above 20% so far (at 19,96% now) and I haven't experienced any other disk faults.

Sometimes this happens within 5 minutes of booting up, sometimes it happens hours after, Windows "freezes": while the already running applications keep running as normal (until they need to save to C:...), I can't launch any new applications - including File Explorer and Task Manager - nor load any websites in already running browsers. This has been happening for about 18 months so far, and it happens 2-4 times a month and doesn't seem to be getting neither more nor less frequent.

When I restart and open BIOS, my SSD is no longer on the list of boot priority. After manually cutting down power for 10 seconds, the SSD always shows up again on the list, but I need to manually set it as #1 on the boot list, because its absence causes the HDD to move up.

The odd thing here is that the SSD has never disappeared from the BIOS without the freeze occuring in Windows first. Which is unlike many of my Google search results, where other people's NVME disks disappear on BIOS load.

With all of that, I'm at a loss whether the issue with the SSD, the motherboard, Windows 10, unrelated software (Comodo Free Antivirus?), or a combination of the former.

What can I do to fix this issue?

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This question had hardware-Windows interaction, but crashes there seem consistent and much more severe. This question had a wholly different issue, since my SSD is visible in BIOS when it works.

Answer 1

SFC is not a good repair program. The fact that it found things to fix means that some Windows programs were not right for your Windows version.

To be sure that all Windows programs are of the same level requires to Do a Repair Install of Windows 10 with an In-place Upgrade.

This operation is the same as a major Windows update, so take the same precautions. It will conserve your apps and almost all settings.

Answer 2

The following two commands below seemed to fix the issue for several months, before it started appearing intermittently a month or so ago, and returned with force yesterday. So you might* need to run these periodically.

Open Command Prompt as an admistrator, run:

Dism /Online /Cleanup-Image /RestoreHealth

which should return a message that ends with:

The operation completed successfully.

and then run:

sfc /scannow

which should return a message containing:

Windows Resource Protection found corrupt files and successfully repaired them. For online repairs, details are included in the CBS log file located at windir\Logs\CBS\CBS.log. For example C:\Windows\Logs\CBS\CBS.log. For offline repairs, details are included in the log file provided by the /OFFLOGFILE flag.

If there were any problems fixed by the latter, opening C:\Windows\Logs\CBS\CBS.log might contain explanation of the fixed problems, like:

00000080 Warning: Overlap: Directory ??\C:\Windows\System32\drivers\en-US\ is owned twice or has its security set twice Original owner: Microsoft-Windows-Foundation-Default-Security.Resources, version 10.0.19041.1, arch amd64, culture [l:5]'en-US', nonSxS, pkt {l:8 b:31bf3856ad364e35} New owner: Microsoft-Windows-Foundation-Default-Security.Resources, version 10.0.19041.1, arch amd64, culture [l:5]'en-US', nonSxS, pkt {l:8 b:31bf3856ad364e35}

If my experience is anything to go by, running these every 2-3 months or so should prevent any of these specific crashes from happening.