Every time I boot up my PC, I see this message after the BIOS splash screen: boot selection failed because a required device is inaccessible 0x000000f

From then, only Windows 10 will only boot when a recovery or installation image is available from USB or Optical drive.

Tried the following without solving the issue:

In Windows RE (Recovery Environment)

  • Bootrec
    • /fixmbr - Fix Master Boot Record (successful)
    • /fixboot - Fix Boot (successful)
    • /rebuildbcd -Rebuild Boot Configuration Data (requested system device cannot be found)
  • Chkdsk (no errors)

In Windows 10

  • Automatic Repair
  • Reinstallation of Windows 10 while saving profile and apps

When scanning for OS /scanos, I see 2x Windows Installations on the D: Drive: Windows and Windows.old

However when booted in Windows 10, the Windows system files are located on C: drive, not D.

My PC: HDD Labels

  1. How do I reconcile the two label differences?

    • Is that why the BIOS cannot see the C drive because it thinks it is D?
  2. Is there anything I can do, short of a clean install?

  • Existence of Windows.old simply means you recently (in the last 14 days) upgraded to the current feature update 1607. No; D drive is normal when boot WinRE – Ramhound Feb 27 '17 at 4:35
  • What style is hard disk? MBR or GPT? – snayob Mar 1 '17 at 23:27
  • @snayob: GPT (Samsung SSD 840 Series with the Windows Installation) I have 2 other HDDs connected. The 1TB drive can be removed and Windows can boot. However, if I remove the 500GB drive with most of the installed apps, Windows won't boot. These two other drives says MBR in Disk Management. – skulldragons Mar 2 '17 at 5:45

For booting a GPT disk with Windows 7/8/10 by UEFI firmware 3 partitions on disk are needed:

  1. EFI System partition (with boot files)

  2. MS Reserved partition

  3. Windows partition itself

If all needed partitions are present on disk you can write/rewrite boot files with:

bcdboot W:\Windows /s Z: /f UEFI

where W: is Windows drive, Z: is EFI System (use diskpart.exe to map EFI System). You should substitute the drive letters in example command with the mappings on your system.

Don't forget to boot Windows installation DVD/USB the UEFI way!

EDIT: EFI System is not mapped usually to a drive letter. You can use diskpart.exe on admin command prompt, then "list disk", select disk number that has EFI System with "select disk 0" (or 1), then "list part", then "select part 1 or 2 or 3 (whatever EFI System is). Then "assign LETTER=Z". Then "quit".

When you boot from USB it is not guaranteed that Windows partition is mapped to drive C: (when having more hard disks even less guaranteed). If you boot from USB and your Windows partition is mapped to D: - this is OK! Then the suggested command above would be "bcdboot D:\Windows /s Z: /f UEFI". (end of EDIT)

  • I would use C: as the Windows Drive, right? – skulldragons Apr 1 '17 at 18:46
  • Since it's the default drive letter. From the USB Windows installation though, it will be listed as D:. What would Z: be? The USB drive letter? On Disk Management, diskpart.exe, the boot drive is listed as Disk 2. Would I use the number 2? or the Partition label? I do not see anything listed as EFI System The list of Partitions is labeled 1 to 4 in the order of System, Reserved, Primary, Recovery. In Computer Management, the EFI system partition is listed as Healthy, but has no designation. Thank you for the suggestion. – skulldragons Apr 1 '17 at 18:53
  • See more help in added "EDIT" paragraph. – snayob Apr 4 '17 at 3:44
  • Tried these commands. May have broken the system. – skulldragons Jul 20 '18 at 4:40
  • diskpart.exe in command prompt list disk select disk 0 select part 1 assign LETTER=Y bcdboot D:\Windows /s Z: /f UEFI I did this in normal Windows command prompt. Couldn't boot to the UEFI USB. Currently, when trying to boot to Windows, this prompt repeats: "Reboot and Select proper Boot device or Insert Boot Media in selected Boot device and press a key" Trying to boot to UEFI right now. – skulldragons Jul 20 '18 at 4:46

Your Answer

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

Not the answer you're looking for? Browse other questions tagged or ask your own question.