Boot-Repair-Disk
Boot-Repair-Disk is a handy tool to own if you have both Windows and Linux OS. Simply download and burn the .ISO to create a rescue disk that can have you up and running in virtually no time at all. It has been designed to work on any PC with any operating system.
Boot-Repair-Disk is a simple tool to repair frequent boot issues you may encounter in Ubuntu, such as when you can't boot Ubuntu after installing Windows or some other Linux distribution. Or, when you can't boot into Windows after installing Ubuntu, or when GRUB is not displayed.
Key features include:
Easy to use.
Helpful (Boot-Info summary to get help by email or on your favorite forum).
Safe (automatic backups).
Can recover access to Windows (XP, Vista, Windows7, Windows8).
Can recover access to Debian, Ubuntu, Mint, Fedora, OpenSuse, ArchLinux.
Can recover access to any OS (Windows, MacOS, Linux) if your PC contains Debian, Ubuntu, Mint, Fedora, OpenSuse, ArchLinux, or a derivative.
Can repair MBR-locked OEM computer boot if the original bootsector has been saved by Clean-Ubiquity.
Can repair the boot when you have the "GRUB Recovery" error message.
Options to reinstall GRUB2/GRUB1 bootloader easily (OS by default, purge, unhide, kernel options..).
All in all, if you need access to a non-bootable drive and want something that has a few other features, such as tools for UEFI, SecureBoot, RAID, LVM, Wubi, and filesystem repair, then Boot-Repair is good piece of software to have. The downside is the filesize for the boor-repair disc is huge!