By Emily / Last Updated August 6, 2020

Windows failed to start in Windows 10

“Today I was ready to power up my Windows 10 computer as usual, but found that the computer could not be started. The screen is black and an error message appears: Windows failed to start A recent hardware or software change might be the cause. So, what should I do to repair it? Is there any solutions to this problem? All the suggestions are greatly appreciated!”

Windows Fails Boot

Many Windows 10 users may be familiar with this error “Windows failed to start. A recent hardware or software change might be the cause.” This is one of the typical Windows boot errors in Windows 10, Windows 8/8.1, Windows 7 operating system. What leads to this error and how to fix it effectively?

Reasons for Windows failed to start issue

Here we list some common causes of the problem Windows failed to start Windows 10.

1. The hard disk is not well cooled, resulting in too high temperatures during operation.

2. Switching the machine incorrectly, to the voltage is unstable (such as frequent forced shutdown and so on.)

3. Errors on the boot partition.

4. Missing or Corrupted BCD File.

5. The Master Boot Manager is corrupted.

6. Bad or Outdated Driver Issues.

7. The Corruption of System Files.

7 Solutions to “Windows failed to start” error in Windows 10/8/7

If you encountered Windows 10 startup problems, you can follow the below text to boot your computer and fix the Windows boot issue.

Solution 1. Launch Startup Repair

As the screenshot above shows, there are two options for you: Launch Startup Repair (recommended) and Start Windows Normally. If the option “Start Windows Normally” does not work, you can choose the first option “Launch Startup Repair” to fix the problem. Choose “Launch Startup Repair (recommended)”, and follow the hints to finish the repair. If any problem is found, the Startup Repair will fix them automatically. If the problem still persists, try the following solution.

Solution 2. Remove any hardware you recently installed

From the error message, we can get that a recent hardware change might be the culprit. So if you recently installed any hardware such as printers or cameras, you can simply remove all of them, leave only the mouse and keyboard attached and restart your computer. If your Windows can boot up successfully, then the hardware you removed was indeed the cause.

Solution 3. Use the Last Known Good Configuration to start Windows

“Last Known Good Configuration” is a recovery option that Microsoft built into all versions of Windows. It can help solve some boot issues that are caused by a driver update, a newly-applied Windows updates or automatic update, virus, trojans, new installed hardware or software that conflicting with other devices.

Step 1. Boot your computer from the Windows installation disk or DVD, and click “Next” on the Windows Setup window.

Step 2. Click on “Repair your computer”.

Step 3. Then click “Troubleshoot” and then “Advanced Boot Options”.

Step 4. On the Advanced Boot Options screen, use the arrow keys to choose “Last Known Good Configuration (advanced)” , and then press “Enter”. Windows will start normally.

Last Known Good Configuration

Solution 4. Repair BCD files

Disk write errors or power failure could make the BCD files missing or corrupted. Then you will receive the error “Windows failed to start” as Windows 10/8/7 begins to load. Luckily, you can try to rebuild the BCD files using Command Prompt.

Step 1. Boot the computer from the Windows installation media.

Step 2. In the Windows setup window, press on “Shift+F10” to bring out the Command Prompt window.

Step 3. In the elevated window, type the following command and remember to hit on “Enter” after each one.

  • bootrec.exe /rebuildbcd

It will scan for other Windows installations not included in the BCD and ask you if you would like to add one or more to BCD.If this does not help, you can manually set the boot path by typing the following command and hit Enter: bcdboot c:\windows /s c: (Here “c” is the System drive).

Solution 5. Check and fix system drive error

If there are some bad sectors or errors on the system drive, the “Windows fails to start” error might also appear. In this case, you can run some commands to check and fix them.

Step 1. Launch Command Prompt window in WinPE mode (refer to the last solution).

Step 2. Then execute the command: chkdsk c: /f /x /r.

Check C Drive

Solution 6. Scan and restore Windows system files

If your Windows crashes and cannot boot up normally, you can use the System File Checker tool.  It is a utility in Windows 10 for checking for problems with the system files on your computer. Likewise, open the Command Prompt in Windows PE environment and run the command: DISM.exe /Online /Cleanup-image /Restorehealth. This DISM command uses Windows Update to provide the files that are required to fix system file corruptions.

When you see a message that says "The operation completed successfully," type ”sfc /scannow” and press Enter. The sfc /scannow command will scan all protected system files, and replace corrupted files with a cached copy that is located in a compressed folder.

Solution 7. Rebuild damaged Master Boot Record

If all the first 6 solutions do not work as expected, you can rebuild damaged MBR with a free partition manager named AOMEI Partition Assistant Standard. It allows you to create a bootable USB stick for booting computer into WinPE mode, and then use the “Rebuild MBR” feature to rebuild the Master Boot Record.

Step 1. Free download and install the software onto a working Windows computer. Connect an empty USB stick to this computer as well. Run the software and click on “Make Bootable Media” and “Next”.

Make Bootable Media

Step 2. Choose the target USB stick. Click “Proceed” to finish the rest operation. The created bootable USB will contain the pre-installed AOMEI Partition Assistant Standard.

Choose USB Drive

Step 3. Insert the bootable USB drive into the computer with “Windows failed to start”error. Change boot order to boot computer from it. Once you log in, the pre-installed AOMEI Partition Assistant Standard will run automatically.

Change Boot Order

Step 4. Right-click the system disk and choose “Rebuild MBR”.

Rebuild System Disk Mbr

Step 5. Choose a proper MBR based on your system.

Choose MBR Type

Step 6. Click "Apply” and then ”Proceed” to start rebuilding MBR.

Apply

Summary

Now, you should know how to fix the error “Windows fails to start” in Windows 10, Windows 8 and Windows 7. If none of those solutions work, you might have to reinstall Windows 10 from scratch. To avoid such similar errors and OS re-installation in the future, it is a great idea to transfer OS to another new drive as a backup.