My Lexar NM790 4TB SSD, mainly used for game installations, suddenly disappeared from Windows Explorer. Event Viewer reported Event ID 51: an error was detected on the device during a paging operation. The drive was also missing from UEFI, but it reappeared after exiting UEFI and rebooting.
I ran `chkdsk E:` without the `/F` option, so it only performed a read-only check. It reported many corrupt NTFS attribute records, orphaned file records, and eventually said that errors were found but CHKDSK could not continue in read-only mode. Hardware monitoring software still reports 100% remaining lifespan and no warnings.
Could this indicate that the SSD itself is failing, or is it more likely a connection, firmware, power, or file-system problem? I opened the laptop about three weeks ago to clean it, so I am wondering whether the SSD was not seated correctly even though its retaining screw is installed. I want to avoid making the problem worse or permanently damaging the drive. What should I do first, and should I run CHKDSK with repair options?
3 Answers
A SMART health percentage is not a guarantee that the SSD is healthy. It mainly reflects the manufacturer's wear indicators and may not catch intermittent controller, firmware, power, or connection failures. Event ID 51 and disappearing from UEFI are consistent with the drive briefly losing communication. After backing up, check the SSD's full SMART/NVMe log for critical warnings, media errors, error-log entries, temperature, and unsafe shutdowns. If it disconnects again, replace it or use the warranty rather than trusting it for long-term storage.
Treat the drive as unreliable for now. First copy anything you care about from it, even though it is only being used for games. Do not start with `/F`, repeated repair scans, or benchmarks. The fact that it disappeared from UEFI is more concerning than the CHKDSK output because that points to the device or its connection temporarily dropping out, not just an NTFS problem. Reseat the SSD and check for dust or damage, then test it in a known-good system or slot if possible. Also check Lexar's support software for an applicable firmware update, but do not update firmware until important data is backed up.
The read-only message does not mean CHKDSK proved the SSD is permanently read-only. It means CHKDSK found problems but was not allowed to modify the file system because `/F` was not supplied. However, the large number of corrupt records could be the result of the earlier disconnect, and running repair might remove or alter damaged directory information. Once the data is backed up and the drive is stable, you can run a repair check, but I would not use CHKDSK as the first diagnostic step.
Creating a small text file successfully does not rule out a hardware problem. A drive can work normally for a while and still disconnect when it gets hot or is under heavier load.