P
PC FIX
blue screen

INACCESSIBLE_BOOT_DEVICE boot device inaccessible

error meaning

Windows was unable to access the system partition during the boot process.

Frequently Occurring Situations

Unable to boot after changing BIOS storage mode, cloning disk, or updating.

First thing to check

Check whether the boot drive appears in BIOS and whether the storage mode was recently changed.

main causes

  • Change AHCI/RAID settings
  • Missing storage driver
  • Disk connection problem

Step-by-step solution

If it is checked and resolved from above, you do not need to proceed to the next step.

1. Check occurrence conditions

Unable to boot after changing BIOS storage mode, cloning disk, or updating.

Difficulty Easy · Estimated time 5 minutes

  1. Check whether the boot drive appears in BIOS and whether the storage mode was recently changed.

Check points: Record the error code, when it occurred, and any recent changes.

2. Boot Device Inaccessible Troubleshooting Procedure

Windows was unable to access the system partition during the boot process.

Difficulty Moderate · Estimated time 10~30 minutes

  1. If you changed the storage mode just before, restore it to the previous mode. If you don't have a history of changes, don't switch randomly.
  2. If you try startup repair in the recovery environment and the disk is not recognized, check cables and devices first.

Check points: Check if it boots normally in the existing storage mode. Secure important files before recovery.

Frequently Asked Questions

Related PC FIX Issues

Windows blue screen keeps happening

Among Windows problems, “blue screen” symptoms may be related to driver or hardware errors, or memory/storage problems. Record the stop code and when it occurred, then narrow down the cause by recent changes, RAM/storage, and system files.

The computer turns on but does not boot into Windows.

Among boot problems, the “powers on but does not boot” symptom may be related to boot file corruption or storage device issues. Distinguish between the POST stage and the Windows startup stage, then check in that order: external device, boot settings, and recovery environment.

official reference document

Content review date: 2026-10-07

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