My Lexar NM790 4TB SSD intermittently disappears from Windows Explorer and sometimes is not detected in UEFI. Windows Event Viewer reports repeated Event ID 51 errors: an error was detected on the device during a paging operation. After rebooting, the drive sometimes comes back.
A read-only `chkdsk E:` scan reported many corrupt NTFS attribute records, orphaned file records, and other filesystem errors, eventually ending with "CHKDSK cannot continue in read-only mode." I have not run it with `/F` because I do not want to make the situation worse. The drive is mainly used for game installations, but I would still like to avoid losing anything unnecessarily.
HWiNFO reports no warnings and shows 100% remaining lifespan. I opened the laptop about three weeks ago to clean it, so I am wondering whether the SSD is poorly seated even though its retaining screw is installed. What should I check first, and does this indicate a failing SSD, a loose connection, or merely filesystem corruption?
2 Answers
The CHKDSK output means the NTFS metadata is damaged. Because you ran it without `/F`, CHKDSK only detected problems and could not repair them; that message does not by itself mean the SSD has permanently switched to read-only mode. However, filesystem corruption can be caused by sudden disconnects, so repairing the filesystem before securing anything important is risky.
Once the data is backed up, you can run a repair such as `chkdsk E: /f` and monitor whether the drive disconnects again. If it disappears during the repair, continues generating Event ID 51 errors, or is missing from UEFI, stop relying on it and replace it. A clean health report does not outweigh repeated disconnects.
Treat this as a possible hardware or connection problem first, not just a Windows filesystem problem. Event ID 51 combined with the drive disappearing from UEFI suggests the SSD or its M.2 connection is intermittently dropping out. Back up or reinstall anything you care about while the drive is accessible, then shut the laptop down, remove power, and reseat the SSD and its retaining screw. If possible, inspect the connector and test the drive in another M.2 slot or system.
HWiNFO showing 100% life does not prove the drive is healthy; SMART wear indicators can remain perfect while a controller, firmware, power, or connection problem is occurring. Check Lexar DiskMaster for firmware and health information, but avoid firmware updates until important data is backed up.
The drive being screwed down only prevents it from moving; it does not guarantee that the edge connector is fully seated. An intermittent connection can also appear weeks later because of slight movement, heat, or vibration.
A successful text-file write only shows that the drive was writable at that moment. It does not rule out an intermittent hardware fault or explain away the corruption already found.