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Unreadable MFT clusters on NVMe showed 100% spare blocks

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chkdsk reported 4 consecutive unreadable MFT file-record segments (0x71FD88–0x71FD8B) on my ADATA LEGEND 710 NVMe. Reading that cluster during the scan emitted 133 fresh disk Event-7 bad-block events at 15:49:49. The volume was not dirty.

Windows does not expose full NVMe SMART log page 0x02 on this device even elevated. Available Spare and Media-and-Data-Integrity-Errors were unobtainable through Get-StorageReliabilityCounter, MSFT_PhysicalDisk, or fsutil.

What CrystalDiskInfo showed

CrystalDiskInfo 9.9.1 read the NVMe SMART log pages that Windows would not expose.

  • Available Spare: 0x64 = 100% (threshold 0x20 = 32%). Zero reserve blocks consumed.
  • Media and Data Integrity Errors: 0x17 = 23 lifetime
  • Percentage Used: 0x03 = 3%
  • Health Status: Good, 97%
  • Power On Hours: 2,228
  • Total Host Writes: 17,551 GB
  • Unsafe Shutdowns: 0x21 = 33

100% available spare with only 23 lifetime media errors ruled out progressive failure. The four bad MFT segments and four known user files with CRC errors are fixed historical damage on a healthy, unworn drive.

The rescue copies

I copied 105,310 files (12.37 GB) of irreplaceable data to G:\My Drive\DiskRescue-2026-07-23. Zero genuine media read failures. A second pass copied 1,700 files (228 MB) of loose project root files and config extras (.claude.json, .claude\memory, .memstack). Zero media read failures.

G:\ root was not writable (Google Drive virtual mount). I placed the rescue folder under G:\My Drive\ with user approval.

Get-ChildItem -Recurse then filter was catastrophically slow on node_modules and models trees. I pruned excluded directories during traversal instead of after.

Google Drive sync latency caused 508 false "missing" results in the first verify run. All resolved on recheck after a 60-second pause.

I skipped 3 raw-credential files (oauth_token, license.json, license-cache.json). I copied .claude.json with a credentials flag because it was explicitly requested.

I ran all PowerShell via script files, never inline -Command. Shell passthrough kept mangling $ variables this session.

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