Windows Boot Manager (Bootmgr.exe) is Microsoft’s proprietary Unified Extensible Firmware Interface (UEFI) application. Fixing Boot Configuration Data (BCD) errors.Repairing the master boot code and boot sector.How to use Windows Boot Manager to fix Windows 10 boot errors.Using the Startup Repair tool to repair the Boot Loader.Most common problems during the Boot Loader phase.

Enabling and disabling Windows Boot Manager.How do I get the Windows 10 Boot Manager back so I don't have to press enter 'exit' in every time? And how do I get rid of the grub command menu thingy? I keep seeing solutions involving using a bootable DVD or USB, but I don't have one, I have burnable DVDs and USB flashdrives, I tried using the program Microsoft supplied me to make a burn device, but I only get the option to use Windows 10, not the OS that I have, which is Windows 10 Home Edition. All I see is one that says something about ubuntu, which is the one that I'm assuming that I have been booting into. I looked in my BIOS, and I no longer see Windows 10 Boot Manager.

I didn't know what to do, so I searched it up, and found that I still have access to Windows, by typing 'exit' and clicking enter. After doing so, I booted up into the grub menu, where you type commands (not choose and click enter). After that, I thought it was a good idea to reboot my computer. I then expanded the volume of my main disk with all of the unallocated space I had just created. After that, I signed in, searched up disk management, and deleted the Ubuntu Partition (365 GB(ish), along with another partition, that had the same storage as the amount of RAM I have (8 GB). I booted up my computer, was taken to the grub menu like usual, and I booted up using the Windows 10 Boot Manager. I decided that I don't want Ubuntu at all anymore.

So I recently dual booted with Windows 10 and Ubuntu.

Bios windows boot manager