It is required by Windows Boot Manager and replaces the boot.ini that was used by NTLDR earlier. In the case of boot problems, you may be required to rebuild BCD. If this does not help ...

Instead, it provides the boot manager (Windows Boot Manager, BOOTMGR). This manager by default loads Windows but also allows, ...

The bootrec /FixBoot Access is denied error mostly occurs while fixing boot-related issues inside Command Prompt. It is related to the Boot Manager. There are some ...

For example, the mitigations are blocked on Windows Server 2012 and Server ... The April 9, 2024 security updates will block mitigations #2 (boot manager) and #3 (DBX update) on affected systems.