I have a tri boot system. Windows 7 and Ubuntu 12 on the 1st hard disk. I got a new hard disk (external) and installed Ubuntu 14.0 on it and updated the grub on Ubuntu 12, it was successful but when i select Ubuntu 14 on the bootloader menu it gives an error such as 'no such device' ' you have to laod the kernal first' I used this article for help
http://www.dedoimedo.com/computers/ubuntu-14-04-install-guide.html
Download software called (Boot-Repair-Disk) from sourceforge.net and burn to dvd, BOOT to the repair disk. Allow system to fully boot. The screen will show a box that says BOOT REPAIR (repair the boot of the computer) Click on (Recommended Repair) you will have boxes open asking you pertinant Questions, one question will be about your external hard disk, answer questions with yes or no and let software do its thing, exit boot repair disk when it's done, and reboot system and your GRUB screen will give you the options you are looking for. Worked for me more than a few times. This software is FREE :-)
