Is it possible that some recovered files after chkdsk scan may be corrupted?

Question

would like to ask if files recovered from faulty HDD, after chkdsk scan (before it was not possible to copy them) may have been corrupted, despite being possible to copy them all (again; after chkdsk scan). I'm talking about

• Word documents - can they be corrupted after copying and for example impossible to open
• Audio and video files - impossible to open or that files will be interrupted while playing them
• Photo files - can some files may be impossible to open or have some defects?

Or is it the case that if after the chkdsk all files were possible to copy onto another HDD (which before the chkdsk scan were not available to copy), then all of them are fine?

Is there a way to test them (like some sort of scan) other then open each individual file, which would take a very long time, because of the size of recovered files (over 100GB)?

Answer 1

One thing people very often seem to be unaware of is that chkdisk's job is not to ensure the integrity of your files, it's to ensure the integrity of the file system.

This means it will sacrifice any data necessary to achieve its goal.

Answer 2

Running chkdsk may actually be dangerous to your files, although beneficial to the file-system.

If your file-system was corrupted, it may be "fixed" by truncating files, attaching file-segments to the wrong files etc.

For example, if two files were found to share the same data segment on the disk, chkdsk will fix it by ensuring that the shared segment will be part of only one file. If this is the wrong file, then although before running it you had one good file and one destroyed file, after running it you could have two destroyed files.

It is better to run chkdsk to evaluate the problem, before running chkdsk /f to fix it. If chkdsk says it found errors, better backup your data before fixing them.

The only way to find if a file has been corrupted, is unfortunately by checking its contents. You may compare the files with a backup, if you have one, to find if any file has changed its size.