How to Fix BOOTMGR is Missing in Windows 10?

BOOTMGR, short for Windows Boot Manager, is part of the volume boot record that can read Boot Configuration Data (BCD). If the “BOOTMGR is missing Windows 10” error happens, then you cannot boot your computer successfully.  Therefore, it is necessary for you to fix the error when it comes out. 

How to Fix the “BOOTMGR is Missing” Error?

1. Disconnect All External Devices 

If you are trying to boot your Windows 10 from an external hard drive that isn’t bootable, you may encounter the “BOOTMGR missing” error. To fix the error and make sure your computer won’t boot from any non-bootable removable drives, you need to disconnect all of them from your computer, such as USB flash drives, external hard drives, and so on. 

2. Change the Boot Order

If the bootable hard drive is not at the top of the boot order, you may also run into the “BOOTMGR is missing Windows 10” error. In this case, you should boot your computer into BIOS, and then set the correct bootable hard drive as the first boot choice. 

3. Run Startup Repair

You can also try to fix the “BOOTMGR is missing” error by running Windows Startup Repair in Windows Recovery Environment (WinRE).

Step 1: Turn off your computer, and then press the Power button to turn it on. Once the screen lights up, hold the Power button again to turn off your computer. Repeat the operation several times until you see a blue screen with Recovery. 

Step 2: Click See advanced repair options, and then select Troubleshoot in the Choose an option window.

Step 3: Go to Advanced Options > Startup Repair.

After you finish the repair process, restart your Windows 10 to see if the “Boot Manager missing” error has been fixed. 

4. Rebuild BCD

The “BOOTMGR is missing Windows 10” error is possibly caused by the corrupted BCD. On this occasion, I recommend you repair BCD to get rid of the error. To do this, follow the steps below. 

Step 1: In WinRE, go to Troubleshoot > Advanced Options > Command Prompt.

Step 2: Type the following commands in the Command Prompt panel and press Enter after each one. 

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

Step 3: After these commands are executed, restart your computer to see if the “BOOTMGR missing” error has been removed. 

5. Check System Hard Drive

Sometimes, the “Boot Manager missing” error may appear if there are some bad sectors on your system hard drive. On this occasion, you can check your hard drive for errors with the CHKDSK utility. Alternatively, you can use MiniTool Partition Wizard. It’s a comprehensive third-party partition manager and enables you to check your disk health. 

The following are detailed steps for checking bad sectors through MiniTool Partition Wizard. 

Step 1: Connect your USB flash drive to another computer that is running properly. 

Step 2: Download and install MiniTool Partition Wizard. Then launch it to enter the main interface. 

Step 3: Click Bootable Media at the top-right corner to build a bootable USB flash drive. 

Step 4: Click WinPE-based media with MiniTool plug-in to continue. Then select USB Flash Disk and click Yes to start building the bootable media. 

Step 5: After the process finishes, click Finish. Then connect the bootable USB drive with the problematic computer and boot the PC from it.

Step 6: Wait a while and you will enter the main interface of MiniTool Partition Wizard automatically. Select the system disk and choose Surface Test from the left action pane.

Step 7: Click Start Now to execute the scan process. 

Step 8: If any bad sectors are found during the process, they will be marked red. Click here to learn how to deal with these bad sectors.  

Conclusion

All these methods mentioned in this post are available. You can follow them when you are experiencing the “BOOTMGR is missing” error.