I'm at a loss on this one. I have 4 OS's using something like 16 partitions on a single disk. My OS's are Windows, Ubuntu, Mint, Fedora and openSUSE. Windows has a Recovery partition (which is the Windows boot partition) plus its own main partition. Each of the Linux systems has 3 partitions - boot, root, and swap. Plus there is an MBR partition at the beginning of the disk.
Everything was was working fine until I tried to update Ubuntu using the Ubuntu software update app. After that completed, I was no longer able to boot Ubuntu (all I get is a black screen with an underscore character blinking in the upper left corner). All of the other OS's still boot and run fine. So I figured that something got hosed in the Ubuntu partitions, and I used IFW to restore all my Ubuntu partitions from my full disk backup. But that didn't solve the problem. So then I also restored my BootIt partition, MBR partition, and Recovery partition. Same problem. I've restored everything I can think of, but BootIt still won't boot Ubuntu, although all the other OS's still boot and run fine.
Where do I go from here? What could possibly be screwed up that can't be fixed by restoring all the partitions used by Ubuntu and BootIt?
Edit update: My original version of Ubuntu (which worked and was backed up) is version 14.04. I was attempting to update it to 14.10.