INACCESSIBLE_BOOT_DEVICECriticalWindows cannot start because the boot drive is unavailable
What this error means
INACCESSIBLE_BOOT_DEVICE means Windows cannot reach the drive it needs to start from. This usually appears during startup, after a restart, or after a change such as a Windows update, driver installation, disk setting change, or moving the drive to a different computer.
In plain terms, your PC is powered on, but Windows cannot find or read the system drive well enough to continue loading.
Common causes
- 1A storage driver changed or became incompatible
- 2Recent Windows updates or system changes interrupted startup
- 3Disk connection, BIOS/UEFI, or storage mode settings changed
- 4File system or disk corruption on the boot drive
- 5Failing storage hardware, such as an SSD or hard drive
How to fix it
- Restart the computer once. If this happened only once after an update or a sudden shutdown, a simple restart may let Windows start normally.
- Disconnect any new external devices. Remove USB drives, docks, external hard drives, and memory cards, then try starting again. A device that interferes with startup can sometimes trigger this message.
- Check the drive and firmware settings in the startup menu. If you recently changed BIOS or UEFI settings, make sure the computer is still set to start from the correct internal drive. If you are not sure what changed, avoid experimenting with multiple settings at once.
- Try Safe Mode. If Windows starts in Safe Mode, a recent driver or update is a likely cause. From there, you can undo the most recent storage or system change, or use Windows Update to install any pending fixes.
- Run repair tools from the Windows recovery environment. If you can reach recovery options, use the built-in startup repair tools. If Windows still will not boot, try the file repair tools that check system files and the disk structure. These tools can fix common corruption without deleting your files.
- Update or roll back storage-related drivers. If the issue began after a driver change, replace it with a known good version or let Windows reinstall the standard storage driver during the next successful boot. Do not manually remove a driver unless you know it is the one causing the problem.
- Check the drive for hardware failure. If startup failures keep happening, the internal drive may be failing. Back up the drive as soon as you can, then have the computer inspected by a repair professional or the device manufacturer.
Recommended fixes
Restart your device
A restart clears temporary state that often causes transient errors.
- Save your work and close open apps.
- Restart the device from the power menu.
- Reproduce the issue to check whether it persists.
Install Windows updates
- Open Settings > Windows Update.
- Click Check for updates and install everything available.
- Restart if prompted.
Boot into Safe Mode (Windows)
- Open Settings > System > Recovery and click Restart now under Advanced startup.
- Go to Troubleshoot > Advanced options > Startup Settings > Restart.
- Press 4 (or 5 for Safe Mode with Networking).
Update your drivers (Windows)
- Open Device Manager.
- Right-click the affected device and choose Update driver.
- Select Search automatically for drivers.
Run System File Checker and DISM
- Open Command Prompt as administrator.
- Run
sfc /scannowand let it complete. - Then run
DISM /Online /Cleanup-Image /RestoreHealth. - Restart your PC.
Contact Quickfix support
If the issue persists after trying these steps, reach out so we can help.
Visit the contact page and include your scan report code.
When to seek help
Get professional help right away if the computer will not start after several attempts, if the recovery tools cannot find the Windows installation, or if you hear unusual clicking or grinding from the drive. You should also be cautious if the problem began after a power loss, water damage, or a BIOS/UEFI change you are unsure how to reverse.
If the PC contains important files and the drive may be failing, do not keep restarting it repeatedly. That can make recovery harder.
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