0x0000007BCritical severityHard to fix
0x0000007B — INACCESSIBLE_BOOT_DEVICE
Windows cannot access the system partition during startup, causing a blue screen.
- Applies to
- Any Windows PC
- Time to fix
- 30-90 minutes
What it means
This stop code appears when Windows loses access to the boot drive — often after a storage-controller mode change, driver corruption, or disk failure.
Symptoms
- Blue screen on boot with INACCESSIBLE_BOOT_DEVICE
- Boot loop / automatic repair loop
- Occurs after a BIOS or driver change
How to fix it
- 1
Correct SATA/NVMe controller mode in BIOS
15 minutes1. Enter BIOS setup. 2. Set the storage controller to the mode Windows was installed with (AHCI vs RAID). 3. Save and reboot.
- 2
Repair boot files from recovery
45 minutes1. Boot from Windows installation media. 2. Open Command Prompt. 3. Run "bootrec /rebuildbcd" and "sfc /scannow". 4. Reboot.
Frequently asked questions
Will I lose my data?
Usually not — this is typically a boot-configuration problem, not data loss. Back up first if the drive is failing.
Last updated July 13, 2026
Guidance only — always consult a qualified professional or the official service manual before carrying out repairs.