Error $15 occurs when Linux is started.

Error $15 occurs when Linux is started. for Linux: CentOS6.3 problem description 1: After you use a USB flash drive to install the system, you cannot unplug the USB flash drive and access the system again. Problem 2: After the hard disk is installed on the system, the hard disk (compression, expansion, partition, etc.) is modified in Windows...
Error $15 occurs when Linux is started. for Linux: CentOS6.3 problem description 1: After you use a USB flash drive to install the system, you cannot unplug the USB flash drive and access the system again. Problem 2: After the hard disk is installed on the system, the hard disk (compression, expansion, partitioning, and other operations) is modified in Windows. after the hard disk is restarted, the system cannot be started. Www.2cto.com and above are the same type of problem: they cannot find the GRUB boot, so they will enter the GRUB> interface after starting the computer. Problem 1 is that GRUB is started and installed to the USB flash drive by default. problem 2 is that the sda number of the Linux boot disk has changed after the hard disk is modified, and the GRUB boot item cannot be found. The solution is to run root (hd0, x) www.2cto.com x on the GRUB interface, which is the sda number of the hard disk where the Linux is installed. if it is unclear, you can try to setup hd0 one by one from 0. This command is used to set the startup location based on the set root location. if "image and vzlinuz cannot be found" appears ", then try other available x locations in the root. Reboot if the previous two steps are successful, the startup item will be displayed after the restart.