Use EASYBCD to repair the failure, directly using the Startup disk repair, mainly based on this post, to verify the available
http://blog.csdn.net/kevin6216/article/details/7764292
Due to the reload of Windows 7, the original Grub boot menu is missing, fix Ubuntu 12.04 grub Boot specific fix method as follows:
1, using the Ubuntu 12.04 Live CD CD-ROM boot system, start the CD-ROM after the installation and choose the trial;
2. Open terminal, enter terminal command: sudo fdisk-l at this point you can see a list of all the partitions displayed on the entire hard disk, please record the location of the Ubuntu root partition/and/boot partition installation;
3. Enter the command in the terminal:
Sudo-i (get root privileges)
Mount/dev/sdax/mnt (X is the Ubuntu root partition under Record)
mount/dev/sda*/mnt/boot (* for ubuntu/boot partition,/boot no separate partition do not execute this command)
grub-install–root-directory=/mnt//DEV/SDA (Note that this command has two minus bars in front of root)
4. After executing the above steps and commands, restart the system, you will see the familiar Grub boot menu.
Install Ubuntu First, install Windows later, fix boot grub