Unfinished Rebuilding of the EFI boot files in Windows

DaxBot 0 Reputation points
2026-09-08T20:42:29.8066667+00:00

My friend was recently locked out of his pc anytime he used safe boot, i saw a post saying you could do some stuff in command prompt but the final line of the commands listed didnt run because it was "in use by another program." The next day he turned on his pc he couldnt get into windows and windows does not show up on his boot manager. Im assuming he needs to get a thumbdrive with a windows iso and use a command promt inside of it to recover it woutout having to re-install windows but he wants to know if there is anything else he can do since he does not have a thumbdrive avaialble and doesnt want to buy one.These are the commands we tried doing:

mountvol s: /s del s:*.*/f /s /q bcdboot %systemroot% /s S:

Windows for home | Windows 11 | Recovery and backup

3 answers

Sort by: Most helpful
Most helpful Newest Oldest
  1. Ivan B 122.3K Reputation points Independent Advisor
    2026-09-08T21:18:38.72+00:00

    Hi,

    Just to be sure: do you want to recreate the Windows boot drive using WinRE?

    Did you mention that the Windows Boot Manager doesn't appear in the BIOS, or is it booting directly into WinRE (in UEFI mode) from the hard drive?

    Thanks.

    Was this answer helpful?

  2. Craig Long 18,545 Reputation points
    2026-09-08T20:54:40.5366667+00:00

    Try holding down the Shift key while restarting the PC. Then select "Exit and continue to Windows 11."

    Try starting the PC and power it off by holding down the power button. Do this at least three times until you get into Windows Recovery.

    If you are stuck on "Safe Boot," type "System Configuration" in the search box. In "System Configuration", go to the General tab and select "Normal startup" or "Selective startup." Go to the "Boot" tab and uncheck "Safe boot."

    See the AI answer for more options.

    Was this answer helpful?

    0 comments

  3. AI answer

    2026-09-08T20:42:46.4266667+00:00

    Yes. A USB drive is not the only next step.

    Since the system can still reach Windows Recovery Environment, try the built-in recovery tools first:

    1. Open Windows RE.
    2. Try Startup Repair.
    3. If the problem started after recent changes, try Uninstall Updates.
    4. If a restore point exists, try System Restore.
    5. If those fail, open Command Prompt in Windows RE.

    For rebuilding boot files, the supported recovery path is:

    1. Mount the EFI system partition: 
         mountvol s: /s
    2. Recreate the boot files: 
         bcdboot <OSDrive>:\windows /s S: /f ALL
      Replace <OSDrive> with the actual Windows partition letter seen in recovery.

    If the BCD store exists but has wrong or missing entries, back it up first, then correct it:

    bcdedit /export C:\temp\bcdbackup

    Then use bcdedit /set {identifier} option value to correct entries, or if the BCD store cannot be opened or is missing, run:

    bootrec /rebuildbcd

    Important: deleting everything under S:\ is risky because it removes EFI boot files. If that deletion already happened, bcdboot is the documented way to recreate them. If commands report files are in use, run them from Windows RE Command Prompt, not from the normal running Windows session.

    If boot files are still missing after that, and Windows RE recovery options all fail, the remaining documented option is to reinstall Windows by using recovery or installation media.

    If Windows starts again afterward, run:

    sfc /scannow

    This checks for and repairs missing or corrupted protected system files.

    References:

    AI-generated content may be incorrect. Read our transparency notes for more information.

    Was this answer helpful?

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.