How do you get rid of bad files on an external drive

Checkdisk (chkdsk.exe) does not get rid of bad files or check for corrupted files. It checks for file system errors and repairs any it finds, and optionally checks for bad sectors.

Bad or corrupted files cannot be scanned for. They will only become apparent when you start an application which requires a file which is corrupt. Then you will get an error message informing you of a corrupt file.

The only way to be sure of getting rid of bad & corrupt files is to wipe the drive and re-install Windows.