Manually Repair Corrupt Boot\BCD Files on Windows 8

Occasionally, you will need to manually repair the boot files on your computer. To do this, boot into the Windows 8 boot menu, as described previously, and click Troubleshoot -> Advanced Options -> Command Prompt.

To manually repair the boot menu for a BIOS-based computer (for UEFI firmware computers, there are additional notes below) in Windows 8, perform the following procedure:

Step 1. Type BcdEdit /export C:\BCD_Backup (where BCD_Backup is the location at which you want the backup to reside) and press Enter.

This creates a backup of the current boot options menu so that it can be restored if needed.

Step 2. Type C: and press Enter.

Step 3. Type cd Boot and press Enter. This navigates to the Windows 8 boot options.

Step 4. Type attrib bcd -s -h -r and press Enter. This allows you to modify and overwrite the boot options.

Step 5. Type ren C:\Boot\bcd C:\Boot\bcd.old and press Enter. This renames the current boot file.

Step 6. Type Bootrec /RebuildBCD and press Enter to force Windows 8 to rebuild the boot menu from scratch.

If you have a dual-boot system, this command might only restore Windows 8 to the boot menu. To restore other operating systems afterward, see the instructions later in this chapter.

If you are using a computer with UEFI firmware, the BCD registry file is located instead in the EFI system partition. This doesn’t have a drive letter associated with it. You can still use the BootRec command, but you should skip steps 2 through 5.

If you need to reimport the backed up BCD file, use step 1 with the /import switch.

The following are other switches you can use with the Bootrec command to perform other actions on the Windows 8 boot menu:

1. /FixMbr This creates a new Master Boot Record file for the disk and can be used if the MBR is corrupt.


2. /FixBoot This switch writes a new boot sector to the disk. Use this if the boot sector has been replaced with a non–Windows 8 sector or if it is corrupt.


3. /ScanOS This scans your hard disk(s) for compatible operating systems and reports back the relevant details so that you can manually add them to the boot menu.

Sometimes Windows 8 won’t start even after repairing the boot system. There is little else you can do at this point but reinstall the operating system. I always recommend, therefore, that you keep a System Image Backup copy of Windows that can be restored in the event of this type of disaster.