How to Format a Corrupted External HDD
Using an external hard drive is a good way to back up your computer's information. But if the external hard drive has been corrupted, it can't be used with your computer. One way to try to fix this problem is to reformat the drive and wipe it of any information. This will reset it to its initial factory settings.
Click the "Start" button on the taskbar.
Click "Run" from the list of options in the menu window. A text box will appear on screen.
Type "cmd" in the text field and click "OK." A command prompt window will open.
Type "format /FS:FAT32 X:" in the text field in the command prompt window and click "OK." Replace "X" with the drive letter of the external drive. A screen will appear asking you to confirm the format.
Enter "Y" when prompted and the computer will then begin formatting the corrupted drive. The status bar on screen will inform you when the format is complete.