A friend's NVMe M.2 drive was the only storage device in his PC. After repeated crashes, Windows eventually stopped booting. The drive is detected when connected to another computer, and diagnostic tools report that its general health appears normal. Windows recovery options and Startup Repair do not work, and changing UEFI settings has not changed the result. A Windows 11 installation USB reported a disk error and attempted repairs, but the system still returned to the recovery screen. It now displays error 0xc000000f, indicating that the Boot Configuration Data could not be read. I would like to preserve the files if possible and repair the boot installation, but I do not have enough spare storage to make a straightforward 1:1 copy of the entire 1 TB drive. What is the safest next step, and is there a way to back up or clone the important data before attempting a repair or reinstall?
2 Answers
Before making more repairs, prioritize copying or imaging the important data. A compressed backup may be smaller than the full capacity if the drive has unused space, but it still needs enough room for the actual files and should be verified afterward. If the drive is BitLocker-encrypted, you will need the recovery key. Once the data is safe, boot a Windows PE or installation environment and rebuild the boot files on the existing Windows installation. Typically this involves identifying the Windows and EFI partitions, assigning them drive letters, and running the equivalent of `bcdboot C:Windows /s S: /f UEFI` with the correct letters. Be careful, because using the wrong partition can overwrite the boot files or make recovery harder.
If rebuilding the bootloader does not work, another option is to preserve the data partition while reinstalling Windows. Move the files you need into a separate partition or external backup first, then reinstall only after confirming the files are readable. Do not rely on Startup Repair or repeated disk repairs as a backup strategy. Also be cautious with CHKDSK and similar tools: they can fix filesystem structures, but on a failing or unstable drive they may make damaged files harder to recover. If the drive starts reporting errors, disconnect it and image it with a recovery-oriented tool before continuing.
The 0xc000000f message points to missing or corrupted boot configuration, but it does not prove the rest of the Windows installation is healthy. I’d treat the data as the priority and only attempt a clean installation after securing a verified copy.
I’ll try using a Windows PE environment and identify the EFI and Windows partitions before rebuilding the boot files. I’ll also avoid making further changes until I have a usable backup.