How to Recover Data from .CHK Files
Windows CHKDSK dropped .chk files in a FOUND.000 folder. They are salvaged fragments. Here is how to recover what you can.
Identify what each .chk really is
- Copy the
.chkfiles out ofFOUND.000to a working folder so you don't lose them. - Open one in a text or hex editor and read the first bytes:
%PDF= PDF,PK= Office/ZIP,ÿD8ÿ= JPEG,ID3= MP3. That signature tells you the real type. - Rename the file with the matching extension (e.g.
FILE0000.pdf) and try opening it in the right program.
Do it in bulk
A free file-type detector (e.g. TrIDNet or the file command on Linux/WSL) scans a whole folder of .chk files and reports each type, so you can rename dozens at once instead of one by one.
When they are worth keeping
CHKDSK creates these only after it salvaged data from a damaged disk, so the original names and types are lost and some fragments are incomplete. If your files are all intact elsewhere, the FOUND.000 folder is safe to delete. If you lost data during the disk error, inspect these before removing them.
FAQ
How do I open a .chk file?
Inspect its header in a text/hex editor or a file-type detector to learn the real type, then rename it with that extension (e.g. .pdf, .jpg) and open it in the matching program.
What is the FOUND.000 folder with FILE0000.CHK inside?
A hidden folder CHKDSK creates to hold fragments it recovered from a damaged disk. The original filenames and extensions are lost.
Can a tool identify many .chk files at once?
Yes — use TrIDNet on Windows or the 'file' command on Linux/WSL to scan the folder and report each file's real type for bulk renaming.
Is it safe to delete .chk files?
Yes, if your data is intact elsewhere. Only inspect them first if you actually lost files during the disk error that triggered CHKDSK.