How to Fix an MBR Inaccessible External Hard Drive

Techwalla may earn compensation through affiliate links in this story. Learn more about our affiliate and product review process here.
How to Fix an MBR Inaccessible External Hard Drive
Image Credit: amnachphoto/iStock/Getty Images

Numerous computers include the ability to boot from an external hard drive. Microsoft Windows-based computers use the Master Boot Record, or MBR, partitioning scheme to separate hard drives into distinct data areas. If the MBR portion of the hard drive becomes corrupt, the computer cannot boot to that hard drive. You may receive an error that the drive is inaccessible or unmountable. Boot with the Windows installation disc and perform a few specific commands to fix an external hard drive with a corrupt MBR.

Advertisement

Step 1

Connect the external USB hard drive to the computer.

Video of the Day

Step 2

Insert the Windows installation disc into the disc drive, then restart the computer.

Step 3

Boot from the CD. Press a hot key to select the CD drive. Common hot keys are Esc, F8, F10 and F12.

Advertisement

Step 4

Click "Repair Your Computer."

Step 5

Click "Command Prompt."

Step 6

Type the drive letter of the external device, followed by a colon, into the prompt. Press Enter. For example, type "E:" without quotes, then press Enter.

Advertisement

Advertisement

Step 7

Type "bootrec /fixboot" without quotes, then press Enter.

Step 8

Enter "bootrec /fixmbr" without quotes. Press the Enter key.

Step 9

Restart the computer.

Video of the Day

Advertisement

Advertisement

Report an Issue

screenshot of the current page

Screenshot loading...