Fault symptom:
Bootmgr startup error, such as bootmgr is missing; bootmgr is compressed chainloader/bootmgr
.
Cause analysis:
Bootmgr is not properly guided.
Solution:
1. The error message "bootmgr is missing" is displayed.
This is because the system boot file is lost or the system partition is not set to an active partition. We can use the system installation disc to fix the problem and start the computer and insert it into the system installation disc, set the BIOS to boot the disc or use the shortcut key (for example, the Lenovo machine is the F12 key), and press enter.
Press any key when the following screen is displayed;
On the installation page, select repair computer;
The repair screen is displayed. Select the first item to start the repair;
The computer will automatically search for the partition where the system is located. If there are multiple operating systems, select the partition where the system you want to start is located and click next;
After the repair is completed, the following screen will pop up. Click Finish. After the computer restarts, it will normally enter the system. If the selected active partition is incorrect, we can use PE to adjust the active partition. Here we will briefly introduce how to start PE, right-click management, and choose disk management;
Depending on the system installation, right-click the partition to be activated and select to mark the partition as an active partition;
Select Yes to restart the computer.
In addition, if the disk has no system or the installation process is interrupted or the hard disk is formatted, the above repair method is invalid and the operating system needs to be re-installed.
2. The bootmgr is compressed prompt is displayed.
This is because the partition where the system is located is compressed. We can start PE and decompress the partition to eliminate the fault.
Start PE, open the computer, find the disk where the system is located, right-click and select Properties;
Remove the compress drive from the General tab to save disk space (C) check box in front and click OK to restart the computer for troubleshooting.
3. The chainloader/bootmgr prompt is displayed.
This problem is generally caused by incorrect multi-system installation methods, which leads to an MBR exception in the master boot record of the hard disk. We can fix the MBR to eliminate the fault. Two methods are introduced.
1. You have fixed the system installation disc. Select a command prompt on the system recovery option interface;
Enter the command bootrec/fixmbr or bootsect/nt60 sys/mbr. Press enter and restart to repair the MBR.
2. You can also use a third-party software under PE to repair MBR. For example, start DISKGENIUS under PE, select the hard disk where the system is located, and click hard disk-re-create master boot record.
