What does “file record segment is unreadable” mean?

That NTFS could not read a record in its master file table — the database holding one entry per file, containing the name, timestamps and a list of which clusters hold the contents. The record failed, not necessarily the file.

Why did a whole folder disappear?

Because a directory is itself a file whose contents are an index of what it holds. One unreadable record belonging to a directory removes the index of everything beneath it — the files remain intact with nothing connecting them to a path.

Are the files recoverable?

Usually. For anything but very small files the record holds pointers rather than data, so the contents are intact and merely unreachable. Very small files stored inside their own record are the exception, and those are lost with it.

Only after checking SMART and copying off what you can. chkdsk removes records it cannot reconcile rather than reconstructing them — a genuine fix on healthy hardware, and destructive where bad sectors sit under the MFT.

Why do recovered files sometimes lose their folder structure?

Because the individual file records survived and the directory index tying them together did not. The contents come back correctly; the arrangement has to be rebuilt separately, and is not always possible.

How do I know if the drive is failing or this was one event?

Watch whether it spreads. One affected folder after a power cut is an event. The same error appearing on new files over days or weeks means the disk is deteriorating — check reallocated and pending sector counts.

chkdsk · MFT damage

This error names the exact structure that failed.

Unlike most Windows messages, this one is precise: a record in the master file table cannot be read. Understanding what that record is explains both why a single file vanished and why an entire folder tree can go with it.

Failing drive recovery →01223 655015

What a segment is

A few vs hundreds

From £300 +VAT

// the short version

How many, is the answer.

Each segment is a one-kilobyte record covering a single file. A handful of unreadable ones is a local defect. Hundreds means the region holding the table itself is going, which is a different conversation.

1 KB

Per segment

$MFT

Where they live

Count

The diagnosis

£300

From, +VAT

×If chkdsk is producing these by the hundred, stop it and don’t run it again. Each pass forces the drive to re-read the same failing sectors, and chkdsk resolves what it cannot read by discarding records — which is exactly the information a recovery would use to rebuild the file system.

// an NTFS message

The index is damaged, not necessarily the files.

NTFS keeps a master file table listing every file on the volume, and each entry is a file record segment. This error means one or more of those records cannot be read — the index describing where a file lives has been damaged, which is not the same as the file itself being damaged.

It usually appears during a chkdsk run or on boot, and it points at sector-level problems in the region holding the MFT. That region is small and heavily used, which is why it degrades early on a failing drive.

The important thing is what you do next, because the standard advice is to let chkdsk repair it and that advice is frequently wrong.

// what to do

Two options, and they diverge sharply.

If the data matters: stop. Chkdsk repairs the file system by discarding what it cannot reconcile. It makes the volume consistent, which is not the same as making your files available, and it writes to a disk that is already failing.

If the data does not matter: let it run. Where the volume is a system disk you intend to rebuild anyway, chkdsk may get it bootable again. That is a legitimate use.

Either way, check the drive health. This error rarely appears on a healthy disk. Read the SMART data before deciding — reallocated or pending sectors climbing means the hardware is the problem.

Do not repeat it. Running chkdsk several times on a degrading drive compounds the damage each pass.

// questions

Answered.

Only if you are prepared to lose whatever it cannot reconcile. It prioritises a consistent file system over your files.

Usually, yes. The MFT region degrades early because it is small and constantly written. Check SMART before assuming otherwise.

Frequently. The records describing them are damaged and the data itself is often intact and reachable by other means.

From £300 +VAT, fixed in writing after the free diagnostic.