What does “the file or directory is corrupted and unreadable” mean?

That NTFS could not read or interpret the record describing that file, not that the contents are damaged. The data is usually still sitting in its clusters, untouched — what has broken is the entry pointing at it.

Why has a whole folder disappeared?

Because directories are files too, and their contents are lists of what they hold. Damage one directory record and everything beneath it becomes unreachable at once, while remaining physically present on the disk.

Only after checking SMART and copying off what you can. chkdsk repairs by discarding records it cannot reconcile — on a healthy drive that is a genuine fix, but on a drive with bad sectors it can delete entries a recovery would have rebuilt.

What causes this error?

Most often an interrupted write — a power cut, a forced shutdown, a drive unplugged too early. It can also be bad sectors falling under the master file table, which produces the error while the rest of the disk reads perfectly.

Is the data recoverable?

Usually, and often completely. NTFS keeps backup copies of critical records, so the structure can be rebuilt from those rather than by deleting anything. Recovery runs against a read-only image, so nothing gets worse while it is attempted.

How do I know if it is one event or a failing drive?

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

NTFS error · explained

The file is fine. The record pointing at it is not.

NTFS keeps an entry for every file and folder, recording which clusters hold the contents. This message means it failed to read that entry — not the contents, which are usually still sitting exactly where they were.

Corrupted file recovery →01223 655015

Index damage, not data

Bad ejection or bad sectors

From £300 +VAT

// the short version

The index entry failed. The file didn’t.

NTFS describes every file and folder in a record in its master file table. Lose the ability to read that record and Windows declares corruption, while the contents sit perfectly intact a few clusters away.

$MFT

Where it breaks

Eject

Commonest cause

48 hr

Free diagnostic

£300

From, +VAT

×Windows will offer to scan and fix the drive. On a failing disk, don’t accept. chkdsk rewrites the file table to make it internally consistent, and it achieves that by discarding entries it cannot reconcile — which is precisely the information a recovery would have used.

// a file system message

The structure is damaged, not necessarily the content.

This is Windows reporting that it cannot make sense of the entries describing a file or folder. NTFS keeps an index of everything on the volume, and this message means the part of that index it needs is unreadable.

The content itself is frequently intact. What has been lost is the description of where it lives and how big it is, and that is a different and considerably more recoverable problem than the data being gone.

The standard advice is to run chkdsk. If the data matters, that advice is usually wrong.

// why not chkdsk

It repairs the volume, not your files.

It writes to a disk that is already struggling. On a drive with failing sectors, that write frequently cannot complete, and an interrupted repair leaves things worse.

It discards what it cannot reconcile. Chkdsk optimises for a consistent file system. Where an entry cannot be repaired it is removed, and your file goes with it.

It gives no preview. You do not get to see what will be lost before it happens, and there is no undo.

Check the drive health first. This error rarely appears on a healthy disk. Read the SMART data before deciding anything.

// questions

Answered.

Only if the volume matters more than the files on it — a system disk you intend to rebuild anyway, for instance. Otherwise, no.

Usually not. The index describing it is damaged and the content is frequently intact and reachable by other means.

That points at sector-level damage rather than a file problem. Stop using the drive and check its health.

From £300 +VAT for a drive, £250 +VAT for cards and USB media, fixed after the free diagnostic.