Ubuntu/Windows dual-system repair guide

Ubuntu/Windows dual-system repair guide first note: Install Ubuntu (or Ubuntu series) without fixing the boot if Windows exists. Grub automatically searches for systems that exist in the hard disk. If Windows is installed on the premise that Ubuntu exists, it is not so good luck... ubuntu/Windows dual-system repair guide first note: Install Ubuntu (or Ubuntu series) without fixing the boot if Windows exists. Grub automatically searches for systems that exist in the hard disk. If Windows is installed on the premise that Ubuntu exists, it is not that good luck. You have to fix the issue on your own. But how to fix it? Don't worry. since grub can automatically search for the system on the hard disk, you only need to reload grub once. But we can't even access the Ubuntu system. how can we reinstall grub? Silly! we have a ubuntu boot disk! In the BIOS, set the ubuntu boot disk to start and select Try Ubuntu. if you select Chinese, it must be "Try Ubuntu". then enter the temporary ubuntu system and open Terminal, perform the following operations: 1. sudo-I 2. fdisk-l 3. mkdir/mnt/temp 4. mount/dev/sdaX/mnt/temp // note that the/dev/sdaX here is the drive of your root directory. mount/dev/sdaY/mnt/temp/boot // note that the/dev/sdaY here is the drive where your boot is located 6. grub-install -- root-directory =/mnt/temp/dev/sda 7. reboot! The following describes the principles. First, we use the Ubuntu boot disk instead of the Ubuntu system in the hard disk, but we need to load the Ubuntu system in the hard disk in this system, then, reinstall the existing Ubuntu system. Of course, the premise for grub to be able to reinstall is to load boot, otherwise it will be a waste of effort. Now, after reboot, you will find that your grub is back and the dual-system era has started!