Windows PC Failure to Boot (no boot device)

Master Boot Record Recovery:

Note--If you remove a Linux install in a Windows/Linux dual boot environment, you will need to replace grub loader with the Windows MBR using the steps below...

Here is a guide for fixing boot problems on Windows 10 and Windows 11 PCs, for anyone with a non-technical background. This covers typical issues and steps anyone can follow to get their computer running again, without assuming IT knowledge.

Common Boot Issues in Windows 10/11

• Windows won't load: PC powers on, but the screen stays black, or you see an error that no boot device was found.
• Boot loop: Windows keeps restarting but never loads into the desktop.
• Strange error messages: "Disk Boot Failure," "Missing Operating System," or blue screen errors appear before Windows starts.

Initial Steps Before Attempting a Repair

• Make sure your PC is fully powered off, and check all cables are secure.
• Unplug any extra USB drives, SD cards, or DVDs. Sometimes the PC is trying to boot from one of these instead of the hard drive.
• If using a laptop, try removing the battery if removable, and reinstalling the battery.
• Try Windows Automatic Startup Repair

1. Power on the computer.
2. As soon as the manufacturer logo appears, immediately press and hold the power button for 10 seconds to force shutdown. Repeat this process 2-3 times. On the next restart, Windows should automatically prompt “Preparing Automatic Repair”.
3. Follow on-screen instructions. Select your account, and enter password if asked.
4. Click "Advanced options," then "Troubleshoot," then "Startup Repair." Windows will try fixing boot problems on its own.

Manual Recovery Console Fixes

If automatic repair doesn't work, use the Command Prompt in Windows Recovery:

1. Boot the PC, then interrupt it as above, or use a USB install stick (Microsoft site provides free downloads for Windows 10/11).

2. Boot from the USB stick. Choose “Repair your computer,” then “Troubleshoot,” then “Command Prompt”.

3. Type each of these commands, one by one, pressing Enter after each:

• bootrec /fixmbr
• bootrec /fixboot
• bootrec /scanos
• bootrec /rebuildbcd

      4. See if Windows can now boot up.

What to Do if Nothing Works

• If these steps fail, there may be hardware issues (like a failing hard drive) or more severe Windows corruption.
• Contact local tech support or the device manufacturer for professional assistance if you’re stuck.
• If you have a backup, you can restore your system from it using the Windows Recovery tools.

Key Tips

• Remove extra disks/media before troubleshooting.
• Use Windows Automatic Repair first, before advanced tools like Command Prompt.
• If recovering from a dual-boot setup (had Linux with Windows), restoring the Windows master boot record might be needed using the commands above.

This guide is meant to help anyone restore their PC by following straightforward steps, even with minimal prior experience with Windows repairs.

Updated 9/20/25