Fix Windows Failed to Start: Step-by-Step Guide

This guide walks you through the most common fixes for the “Windows failed to start” error, which appears when your PC can’t boot into the operating system. You’ll learn how to use the built-in Windows Recovery Environment to repair startup problems, restore system files, and get back to your desktop without losing your personal files.

What You’ll Need

A Windows PC that shows the “Windows failed to start” blue screen or a similar boot error
Your Windows installation media (USB or DVD) OR access to the Advanced Startup Options menu (usually triggered by interrupting the boot process three times)
A second working computer (optional, for creating installation media or downloading tools)
A USB drive with at least 8GB of space (only needed if you must create installation media)
Patience – some repairs take 15-30 minutes

Step-by-Step

Enter the Windows Recovery Environment. If your PC shows the blue “Windows failed to start” screen, click “Advanced options” or “Repair your computer.” If you don’t see these options, power off your PC completely, turn it on, and when the Windows logo appears, press and hold the power button to force shutdown. Repeat this three times. On the fourth boot, Windows should display “Preparing Automatic Repair” and then take you to the recovery menu.
Choose Troubleshoot. From the blue screen, select “Troubleshoot” (sometimes labeled “Advanced options”), then “Advanced options” again if needed. This opens the main recovery menu with several repair tools.
Run Startup Repair first. Select “Startup Repair” (or “Startup Repair” under “Advanced options”). This tool scans your boot files and tries to fix problems automatically. It may take 10-20 minutes and might restart your PC. If it succeeds, Windows will boot normally. If it fails, you’ll return to the recovery menu.
Use Command Prompt for boot file repairs. If Startup Repair doesn’t work, go back to the recovery menu and select “Command Prompt.” Type the following commands one at a time, pressing Enter after each: bootrec /fixmbr, bootrec /fixboot, bootrec /scanos, bootrec /rebuildbcd. When prompted to add an installation to the boot list, type Y and press Enter. Close the Command Prompt and restart your PC.
Run System File Checker (SFC) and DISM. If boot repairs don’t help, open Command Prompt again from the recovery menu. Type sfc /scannow /offbootdir=C:\ /offwindir=C:\Windows and press Enter. Wait for it to finish. Then type DISM /Online /Cleanup-Image /RestoreHealth (if Windows is on your main drive) or DISM /Image:C:\ /Cleanup-Image /RestoreHealth and press Enter. These tools repair corrupted system files. Restart after completion.
Try System Restore. From the recovery menu, select “System Restore.” Choose a restore point from before the problem started (if any exist). Follow the prompts and let your PC restore. This removes recent system changes but keeps your personal files.
Use Safe Mode to diagnose. From the recovery menu, select “Startup Settings” (or “Advanced options” then “Startup Settings”), click “Restart,” then press 4 or F4 to boot into Safe Mode. If Windows loads in Safe Mode, the problem is likely driver-related. Uninstall recently added drivers or software, then restart normally.
Reset your PC. If nothing else works, from the recovery menu select “Troubleshoot” then “Reset this PC.” Choose “Keep my files” to reinstall Windows while preserving your documents, photos, and other personal data. This removes installed apps and settings but is often the final fix before a full reinstall.
Reinstall Windows as a last resort. If Reset fails or you don’t care about installed apps, boot from your Windows installation media (USB or DVD). Choose your language, click “Install now,” and select “Custom: Install Windows only.” Select your main partition and delete it, then create a new one and install Windows. This wipes everything on that drive, so only do this if you have backups or no important data.

Common Mistakes

Skipping Startup Repair. Many users jump straight to complex commands, but Startup Repair fixes the majority of boot problems with one click.
Forgetting to remove external drives. A USB drive or external hard disk plugged in during boot can confuse the boot process. Remove all non-essential USB devices before trying fixes.
Running commands on the wrong drive letter. In the recovery environment, your Windows drive might not be C:. Use diskpart and list volume to check, or the bootrec commands will simply fail.
Interrupting repairs. Startup Repair and SFC scans can take 20+ minutes. Letting your PC turn off mid-scan can make things worse.
Choosing “Reset” without checking backups. Even “Keep my files” can fail, so always back up important data to an external drive before any reset.

Tips

Back up before you start. If you can access your files via another computer or by booting from a Linux live USB, copy your important documents to an external drive first.
Create a recovery drive now. After your PC is working again, create a USB recovery drive (search “Create a recovery drive” in Windows) so future boot problems are easier to fix.
Check your disk health. A failing hard drive often causes boot failures. After booting, run chkdsk /f /r C: in an elevated Command Prompt to check for bad sectors.
Keep Windows up to date. Many boot issues come from buggy updates. Regular updates and driver updates from your PC manufacturer reduce the chance of recurrence.
Disable Fast Startup. This feature can sometimes cause boot problems. In Windows, go to Control Panel > Power Options > Choose what the power buttons do > Change settings that are currently unavailable, then uncheck “Turn on fast startup.”

Troubleshooting

Startup Repair says it couldn’t repair your PC. This is common. Run it a second time – sometimes it needs two passes. If it still fails, proceed to the bootrec commands in Step 4.

bootrec /fixboot gives “Access is denied.” This usually means the BCD (Boot Configuration Data) is corrupt. Try bootrec /rebuildbcd directly, or use the command bcdedit /export C:\bcdbackup then ren C:\boot\bcd bcd.old and finally bootrec /rebuildbcd.

You don’t see the recovery menu at all. Force shutdown three times as described in Step 1. If that doesn’t work, you’ll need Windows installation media. On another PC, download the Media Creation Tool from Microsoft’s website, create a bootable USB, then boot from it and select “Repair your computer” on the first screen.

System Restore shows no restore points. This happens if System Protection is disabled. Skip to the Reset option, or try the SFC/DISM commands first – they can often fix the underlying issue without needing a restore point.

Your PC boots to a black screen instead of the recovery menu. Press and hold the power button to force shutdown, then turn it back on. If it still shows black, try connecting your monitor to a different port (GPU vs motherboard) or resetting your BIOS by removing the CMOS battery for 30 seconds.

After reset, your PC still won’t boot. This points to a hardware issue. Test your RAM with MemTest86 (free tool), check your hard drive’s SMART status, and reseat your RAM and storage cables. If the problem persists, the drive may be failing.

Frequently Asked Questions

Will I lose my files if I use Startup Repair? No. Startup Repair only fixes boot files and doesn’t touch your personal data. Only “Reset this PC” or a clean install will remove your files (and even Reset with “Keep my files” preserves them).

Why does Windows keep saying “failed to start” after every restart? This usually means a critical system file is corrupt, a driver is incompatible, or your hard drive is failing. Work through the steps in order: Startup Repair, bootrec, SFC/DISM, then System Restore. If all fail, test your drive’s health.

Can I fix this without a Windows installation disc? Yes. The recovery environment is built into Windows and accessible via the force-shutdown method in Step 1. If that doesn’t work, you can create installation media for free on any PC using Microsoft’s Media Creation Tool.

How long does Startup Repair take? Typically 10-20 minutes, but it can take longer on older or heavily fragmented drives. Let it finish completely – don’t interrupt it.

What’s the difference between “Reset this PC” and “Reinstall Windows”? Reset reinstalls Windows from a recovery image stored on your PC, which is faster and doesn’t require media. Reinstalling from a USB gives you a completely clean system and can fix issues that Reset can’t. Both remove installed apps.

My PC is stuck in a boot loop – it restarts before I can see anything. Force shutdown three times as described in Step 1 to trigger Automatic Repair. If that fails, you’ll need to boot from a USB drive. On another PC, create installation media, then change your BIOS boot order to prioritize the USB drive.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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