UNMOUNTABLE_BOOT_VOLUME Stop Error – STOP OX000000ED
Cause – Occurs if Windows is unable to access the volume containing the boot files.
Step 1 – Shut your PC off.
Step 2 – Check and verify all hard drive/disk cables are firmly connected to both the motherboard and disk drive.
(Note – Older IDE drives such as ATA-66 and ATA-100 should be using double density 80-Connnector Cables, instead of standard 40-Connectors.)
If the cables are secure and the correct type and you still experience the problem try the following.
Step 1a – Boot from your Windows CD or Bootable USB Flash Drive and Click the repair your computer.
Step 2a – Click DOS prompt
Step 3a – Type chkdsk /f and press enter.
Step 4a – Remove the Windows CD or Bootable USB Flash Drive and restart.