Ubuntu – Boot-Repair made Dual Boot System unusable

bootdual-bootgrub2uefiwindows 8

After an Update to Ubuntu 14.04, the system no longer started and showed the grub rescue prompt. I was able to start from CD by pressing F10 at the beginning to select the boot medium. Then I was able to boot Ubuntu using the Super Grub Disk, updated the Boot-Repair program and started it.
error symbol 'grub_term_highlight_color' not found

I updated grub, boot-repair and the system:

sudo apt-get update
sudo update-grub
sudo boot-repair

and somehow repeated application of Boot Repair managed to break the UEFI Windows Boot process entirely. Now Windows 8 no longer boots, no matter what I do. It returns the errors EndEntire error: premature end of file.. or EndEntire error: cannot load image... The EFI/UEFI boot process for Windows is completely broken.

What I can do to boot Windows again? :-/

Here is the current output of Boot-Repair
http://paste.ubuntu.com/11985798/

Best Answer

The EndEntire error: premature end of file and EndEntire error: cannot load image messages might indicate a problem that needs to be fixed from the Windows side -- namely, damage to the Windows boot loader. (OTOH, if you have a backup of your EFI System Partition, or ESP, from before the error occurred, you may be able to recover by restoring that backup. IMHO, such a backup should be made as a matter of course both before and after installing Ubuntu -- but that's another matter.) If I'm right about this, you'll need to get your hands on a Windows recovery disk, use it to fix the Windows boot loader, and then re-install a Linux boot loader or change the boot order so that what you've got now boots first.

I also recommend you re-read my second response to your answer to your earlier question. In particular, prepare a rEFInd USB flash drive or CD-R and try booting with it. This tool (which I maintain) can boot Ubuntu without GRUB, and can chainload to the Windows boot loader, so if GRUB is acting up, rEFInd can provide a workaround -- either temporary or permanent.

Disclaimer: I'm not a fan of GRUB 2. It's a bloated pig of a program with a finicky configuration file that's so difficult to maintain that GRUB provides a series of scripts to perform that task. The result is like a house of cards -- it holds together OK under optimal conditions, but if anything about your configuration is sub-optimal, the whole thing will come tumbling down and be difficult to put back together again. FWIW, my disaffection with GRUB 2 is what motivated me to fork the earlier rEFIt into rEFInd. GRUB 2 has improved since that time, but the fact that I took on maintenance of an open source boot manager rather than deal with GRUB 2 should say something about GRUB 2's problems, at least in my eyes.

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