Super Grub Disk

Esta es una herramienta para reparar Grub rotos de booteo de varias particiones y sistemas aqui les dejo el dato...

Super Grub Disk (SGD) is a specialty rescue CD for emergency repairs on boot sectors. Despite its name, SGD not only manipulates the Grand Unified Bootloader (GRUB), but also works with the content of other master boot records as well.

SGD is often useful. Here there are some examples:

• GNU/Linux is installed in your pc, you reinstall Windows and GNU/Linux no longer boots as Grub menu no longer appears on boot. You can restore Grub on your MBR automatically.
• You have Windows installed in a second hard disk and it does not want to boot. If you swap it from Super Grub Disk you will be able to boot it.
• You can not boot Windows because your MBR is corrupt or Grub installation is not well done or whatever. With Super Grub Disk you will be able to boot the partition where Windows reside.
• No Active Partition Found message appears. With Super Grub Disk you can activate partitions.

http://www.supergrubdisk.org/category/download/supergrubdiskdownload/