I’ve heard it said, “If it wasn’t safe to run, Microsoft wouldn’t have put it there.”
Unfortunately, it is a little more complex than that. Chkdsk is a windows program designed to fix problems within the NTFS or FAT file systems caused by improper system shut downs or bad sectors on a hard drive. During this process of “fixing” the file system, it may have to drop references to files and or folders, causing the data in the subsequent chains to be lost. This might not be so bad, if there were an undo or revert back to previous state. Rather, once you commit to allow chkdsk to make changes to the file system, they cannot be undone.
Recovery Force recommends making sure data is 100% backed up before running chkdsk on a hard drive, as per these quotes from a page on Microsoft’s website:
Note: When you run the check disk, there are chances of losing data so you can take a backup before running checkdisk.
Important: While performing chkdsk on the hard drive if any bad sectors are found on the hard drive when chkdsk tries to repair that sector if any data available on that might be lost.
In fact, we recommend that you get a full sector-by-sector clone of the drive, to be certain. Not only will the clone help you have a full backup of the drive, it will help you know if there are any bad sectors that you will need to deal with. If cloned with the right tools, it may be possible to keep re-read the bad sectors with various read methods and timeouts that may allow for a more complete clone and less data loss.
If Windows and/or someone is advising you to run chkdsk on your hard drive to “fix” some problems, please stop and make sure that the data is backed up and be aware that this could be a good sign that your hard drive is starting to fail and should be fully tested and replaced, if necessary.
Should you be in a situation where you are not sure what to do next, please feel free to contact Recovery Force (866-750-3169) for some advice.