bad sector of harddisk - disk check and recovery

I got a harddisk from my friend, it maybe broken, so I need to save any remaining data which can be saved.

I can see the drives, but when copy some files, the computer said they are bad and rereadable(not exact phrase).

Then I installed some software, thinking maybe they can check whether and which files are corrupted, then I rebooted the pc.

After the shutdown of the pc, the computer started a disk scan on the harddisk, and I am not awared of any prompt from the pc. Now the scan is running and takes some time to finished.

At the mean time, it found some files and folder are in the bad sector. Then it said the files are replaced by null. And it said it removed a folder because it is entirely unreadable. Actually I don't know what does it mean, **so my question is - What does the scan do when it encounter bad files and folders? Are there any chance I can save the data, maybe with any other software?

By the way, can I stop the scan? I tried to press Esc, Alt+Ctrl+Del, don't work.**

Solution 1:

You can try CTRL+BREAK to stop the execution of scandisk command.

After that, I recommend you using Roadkil's Unstoppable Copier to recover your readable files.

Roadkil's Unstoppable Copier recovers files from disks with physical damage. Allows you to copy files from disks with problems such as bad sectors, scratches or that just give errors when reading data. The program will attempt to recover every readable piece of a file and put the pieces together. Using this method most types of files can be made useable even if some parts of the file were not recoverable in the end.

Solution 2:

"[...] it found some files and folder are in the bad sector. Then it said the files are replaced by null. And it said it removed a folder because it is entirely unreadable.[...] What does the scan do when it encounter bad files and folders? Are there any chance I can save the data, maybe with any other software?"

The scan remaps that bad sector to a good but empty one, the data in that sector is lost. If that sector was part of a file, folder, directory listing etc that logical object now has a bunch of 0 bytes somewhere in the middle, which may lead to subsequent logical errors. Then programs like checkdsk will try to correct those errors, e.g. by erasing the damaged directory entry for a folder (in that case your folder is logically gone, although most of its data are still somewhere on the disk).

It's probably too late now, because you have already let all kinds of software do its 'repairs'.

The best procedure in these cases is:

1) Do not shut down/reboot any more than necessary. If the bad spots are in critical sectors at the beginning of the disk the system may not boot up again.

2) Optionally, try to make an image of the entire disk or in one way or another pull all the important data from the disk. There's lots of variations on how you can do this, but whatever methode you choose, read only!. Do not write to the disk. Pulling it out of your computer and putting it in another computer as a non-primary disk is a good way to prevent software (the OS) from automatically writing to it.

3) Buy a copy of Spinrite and run that on the damaged disk. SR will not just reallocate the bad sectors, but it will keep reading the damaged sectors thousands of times, slightly re-adjusting the disk heads, in an attempt to (statistically) reconstruct the data that was in the bad sector, then write that data to the new sector. Very often this leads to a full recovery without errors.

4) Finally run software that does logical checks on the disk structure, like checkdsk. This could veryy well not find any errors after step 3.

While running, SR will also check for an overheating disk or other potential problems.

Bye Jan