Use diskpart
A common is to use the diskpart utility (available on the Windows 8/8.1 recovery disc/USB) to make sure the UEFI partition has a letter assigned to it. If it doesn’t, you’ll assign it a letter.
The instructions you need to follow are:
- Insert your original Windows 8 installation disc or Windows 8.1 installation USB
- Boot from the disc or the USB
- At the Install now screen, click Repair your computer or press R
- Click Troubleshoot
- Click Advanced options
- Click Command Prompt
- When Command Prompt has finished loading, type:
diskpart
- Press Enter
- The diskpart utility should now be loaded:
DISKPART>
- Type:
sel disk 0
- Press Enter
- Wait for the confirmation message:
Disk 0 is now the selected disk.
- Type:
list vol
- Press Enter
- diskpart will now show the full list of volumes available on your PC
- Find the UEFI volume from the list. This usually has “BOOT” mentioned on the Label column, “System” on the Info column. The Fs column might FAT32 specified. For our example, in the next steps, our UEFI partition will be on Volume 2.
- Type:
sel vol 2
- Press Enter
- Type:
assign letter=G:
- Press Enter
Wait for the confirmation message:
DiskPart successfully assigned the drive letter or mount point.
Type:
exit
- Press Enter
Type:
cd /d G:\EFI\Microsoft\Boot\
Where G: is the drive letter you’ve assigned to your UEFI partition a few steps back.
If the
\EFI\Microsoft\Boot\
folder doesn’t exist (the error message will be “The system cannot find the path specified”), you can run the same command on alternative paths:
cd /d G:\Boot\
or
cd /d G:\ESD\Windows\EFI\Microsoft\Boot\
Remember to replace G: with the UEFI’s partition letter.
Type the bootrec command:
bootrec /fixboot
- Press Enter
- For backup purposes, backup the BCD record of your computer like this:
ren BCD BCD.bak
Recreate the BCD using the bcdboot command:
Bcdboot C:\Windows /l en-us /s x: /f ALL
Where
C:\
is the letter of the drive where Windows 8 or Windows 8.1 is installed on.The
/l
en-us parameter is used for localization: US. You can use ln/en-gb
for UK localization.Press Enter
- You can also run this command too:
bootrec /rebuildbcd
- Press Enter
- Type
exit
in Command Prompt- Restart your computer
- Your Windows 8/8.1 should now boot again
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