[Solved] Can’t Open BIOS Windows Boot Manager Windows Failed to Start

When your computer has problems with the Windows Boot Manager, it may be an unpleasant experience. The Windows Boot Manager is an important component that aids in the launch of your operating system.

Don't panic if you can't access BIOS or are having issues with the Windows Boot Manager; there are various ways you may attempt to get your system back on track. This detailed tutorial will bring you step-by-step directions for dealing with these challenges utilizing a variety of ways.

Why you can’t open BIOS Windows Boot Manager Windows failed to start?

Before we go into the answers, we must first understand why you can't open BIOS Windows Boot Manager and Windows did not boot. The error message Windows Boot Manager boot failed may appear on your computer's screen during the initial phase. The most common reason for this problem is a damaged or corrupted Master Boot Record. 

The reason why the Windows boot manager not working is complicated, but possible reasons are:

• The file integrity is damaged.

• The HDD data cable is not working.

• The BCD file is missed or corrupted due to disk write errors, power outages, or boot sector viruses.

• A corrupted Master Boot Record (the root reason)

How to fix [Can’t open BIOS Windows Boot Manager]

In this part, we’ll show you how to fix Windows Boot Manager failed to start Windows 11/10 via 3 ways.

Way 1. Using Bootrec.exe tool

The Bootrec.exe Tool is a built-in utility in Windows that can help fix issues related to the Windows Boot Manager. This tool is especially useful when the boot manager is not opening correctly or if you are encountering errors during startup.

Step 1. Restart your system and press F8 to see the Windows Recovery Menu.

Step 2. Select "Troubleshoot" > "Advanced options" > "Command Prompt."

Step 3. In the Command Prompt window, type the following commands one by one and press Enter after each command:

bootrec /fixmbr
bootrec /fixboot
bootrec /scanos
bootrec /rebuildbcd
bootsect /nt60 SYS (or bootsect /nt60 ALL)

Step 4. After executing these commands, restart your computer and check if the issue is resolved.

Way 2. Perform a System Restore

Performing a System Restore can be a lifesaver when you're facing issues with the Windows Boot Manager. This solution allows you to revert your computer's state back to a point where it was functioning correctly, effectively undoing any recent changes that might have caused the problem.

Step 1. Restart your computer and boot from the Windows installation disk.

Step 2. Choose to change language & other settings in Windows Setup or not; then, click Next.

Step 3. Click Repair your computer.

Step 4. Select Troubleshoot > Advanced options > System Restore.

Step 5. Choose the target operating system.

Step 6. Click Next in the System Restore wizard.

Step 7. Select the proper restore point and click Next.

Step 8. Confirm your selection and click Finish.

Step 9. Click Yes in the prompt window to confirm system restore.

Step 10. Wait for the restore to complete. Restart your PC.

Way 3. Try a third-party boot manager

For a more advanced and comprehensive solution, you can consider using AOMEI Partition Assistant Professional. This powerful software offers a wide range of features designed to manage hard drive partitions and troubleshoot the Windows Boot Manager error under WinPE.titions and boot settings.

With its user-friendly interface and robust set of features, this tool is perfect for both beginners and experienced users. Whether you're dealing with boot problems, disk partitioning, data migration, or disk optimization, AOMEI Partition Assistant has you covered.

Step 1. Put the USB flash drive to your Windows 10 PC. Run AOMEI Partition Assistant Standard, and select Make Bootable Media under the Tools panel.

Step 2. Click Next at the next window, and choose USB Boot Device.

Step 3. Read the formatting warning and then click Proceed.

Step 4. Then boot your corrupted Windows 10 computer from the bootable media. AOMEI Partition Assistant will automatic run on the desktop then.

Step 5. Select Rebuild MBR.

Step 6. Choose the MBR for your Windows 10 operating system. Hit OK.

Step 7. Click Apply.

Further reading: How to prevent Windows Boot Manager not working

Although there are some solutions save you when you can’t open BIOS Windows Boot Manager and Windows failed to start, in fact, in daily working, you can make some measures to prevent Windows Boot Manager issues or worse cases.

If you’re a UEFI boot bode user, then, you can use the “UEFI BIOS Boot Options Manager” function to back up your Windows boot settings. When some errors happen, you can directly use the backup files to quickly restore your Windows boot.

Click the boot option you want to backup to make a backup so that you can recover if necessary.

Select a location on your PC and click "Save" to save the backup.

Then the backup will create a .PAUB file.

To restore, you can enter the OS via Safe mode to visit your backup file:

Step 1. Click to restore the boot option you just backed up if the partition or boot files get lost or corrupted.

Step 2. Locate the .PAUB FILE you backed up and select it to restore.

Ending lines

Hope the above solutions can help you when you can’t open BIOS Windows Boot Manager Windows failed to start. Because the Windows boot manager file is critical for PC starting, it is secured by the system (hidden and read-only). It is really in the active partition's root directory. It has a System Reserved designation on most PCs. You will be unable to boot into the system if it is damaged.

Aside from being a boot manager, AOMEI Partition Assistant can also clone a drive, migrate an operating system, convert a disk to MBR/GPT without data loss, relocate existing software, and allocate free space... It also includes the Server Edition for Windows Server users, as well as more advanced editions for those with more stringent needs.