How to resolve the issue of being unable to boot after installing CentOS 7.

If you are unable to boot after installing CentOS 7, it may be caused by the following reasons:

1. The location of the bootloader installation is incorrect: When installing CentOS 7, the bootloader needs to be installed in the MBR (Master Boot Record) of the hard drive or the EFI system partition. If the wrong location is chosen during installation, the system will not be able to boot properly. The solution is to reinstall CentOS 7 and make sure to select the correct installation location.
2. If the bootloader is overwritten by another operating system: If you have installed another operating system (such as Windows) before installing CentOS 7, the bootloader of that operating system may have overwritten the CentOS bootloader. The solution is to use a bootloader repair tool (such as Windows’ startup repair tool) to fix the bootloader, and then reinstall CentOS 7.
3. Corrupted boot configuration file: Errors during installation or unexpected system shutdowns can cause the boot configuration file to become damaged. The solution is to use the CentOS 7 installation disc or USB drive to enter recovery mode and repair or regenerate the boot configuration file.
4. Hardware compatibility issue: In some cases, specific hardware configurations may cause CentOS 7 to fail to boot. One solution is to try updating the system’s BIOS firmware or drivers, or to attempt boot tests using a different Linux distribution.

If you are unfamiliar or unsure about the above solution, it is recommended to consult professionals or seek help on relevant technical forums.