Win+ubuntu dual system, reload after win, win destroys grub after restore method

1.sudo-i (or sudo bash)//switch to root privilege 2, fdisk-l//Look at where the Ubuntu partition is, it looks as if it is the following, Device Boot Start End Blocks Id System /DEV/SDA1 * 1 2432 19535008+ C W95 FAT32 (LBA)/dev/sda2 2433 19457 136753282 f W95 Ext ' d (LBA)/dev/sda5 2433 7296 390700 48+ b W95 Fat32/dev/sda6 7297 12395 40957686 7 hpfs/ntfs/dev/sda7 12396 15435 24414062+ linux/dev/sda8 15435 15739 2 440192 swap/dev/sda9 15739 19163 27507712 Linux 3, MOUNT/DEV/SDA9/MNT//hangs in root of the original system 4, Grub-install--boot-di rectory=/mnt//DEV/SDA (here/DEV/SDA is a disk, not a partition) see installation finished. No Error reported. The success of the method in the hands of the courage to re-install Win7, do win7, burning u disk LiveCD, all step-by-step, after restarting the result or tragic grub command line instead of what familiar grub boot Menu! I am dizzy, do not know whether the online method is wrong, I tried several times or failed to solve. There is no way to do something else ... I use LiveCD to enter the system, find the Ubuntu system boot file grub.cfg, write down my system main boot information: root= ' (hd0,7) ', Linux/boot/vmlinuz-2.6.32-24-generic, INITRD/ Boot/initrd.img-2.6.32-24-generic, decided to try to boot under the GRUB command line, after reboot, enter under the GRUB command line: 1.grub>root (hd0,6)//input root (hd0, Press TAB to see the Linux partition 2.grub>kernel (hd0,6)/boot/vmlinuz-2.6.32-24-generic root=/DEV/SDA7//File name can be pressed tab completion, SDA7 is (hd0,6) 3.grub>initrd/boot/initrd.img-2.6.32-24-generic//press TAB to fill the full 4.grub>boot With a disturbed mood, finally see grub in the boot, a familiar Ubuntu interface back! After entering the next update grub will be OK; 1. Open terminal, 2.sudo-i, 3.update-grub,

Win+ubuntu dual system, after reloading win, win destroys grub after the recovery method