What to do if bootmgr is lost and cannot boot

The loss of bootmgr and the inability to boot means that the master boot record of the hard disk is incorrect, resulting in the system being unable to boot. The solution: 1. Press the "ctrl alt delelte" key to restart; 2. Directly press " F2" to enter the BIOS, find the system startup sequence, and then select the system startup disk. After completion, F10 to save and exit; 3. Enter the system startup options and select "Startup Repair".

#The operating environment of this tutorial: Windows 10 system, Dell G3 computer.

What should I do if the bootmgr is lost and cannot be booted?

After the computer is turned on or restarted, it displays: Bootmgr is missing, which means that the master boot record (MBR) of the hard disk is wrong, resulting in the inability to boot the system, which can only rebuild the master boot record, and there is another It may be that system files are missing, causing the system to fail to boot. The specific method is as follows:

1. It means that the bootmgr (boot manager) file is lost and you need to press the [ctrl] [alt] [delelte] key to restart.

2. If it still cannot be started, you can directly press [F2] to enter the BIOS during the boot process, find the system startup sequence, select the system startup disk, and then F10 to save and exit.

3. You can also use [F8] to enter the system startup options and select [Advanced Options]. You can try to select [Startup Repair], [System Restore] and other options to see if you can enter the system normally. .

Booting process

When we press the power switch, the power supply starts to supply power to the motherboard and other devices. At this time, the voltage is not stable yet, and the control on the motherboard The chipset will send and maintain a RESET signal to the CPU to allow the CPU to automatically return to its initial state, but the CPU will not execute instructions immediately at this moment.

When the chipset detects that the power supply has begun to supply stably (of course, the process from unstable to stable only takes a moment), it removes the RESET signal (if the Reset button on the computer panel is pressed manually To restart the machine, the chipset will remove the RESET signal when the button is released), and the CPU will immediately start executing instructions from address FFFF0H.

As can be seen from the previous introduction, this address is actually within the address range of the system BIOS. Whether it is AwardBIOS or AMIBIOS, what is placed here is just a jump instruction, jumping to the real startup code in the system BIOS. .

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