Windows 8 UEFI does not boot [duplicate]

This looks like bug #1091464. Turn off secure boot in the bios system under the section boot, and you should be able to boot Windows.

The suggestion to try this solution is a good one, and Dillmo's suggestion might work, too. I have three other suggestions, though:

• This problem can sometimes be caused by a failure to disable the Windows Fast Startup feature. Note that this is not the same as the "fast boot" feature in the firmware. If left enabled, Fast Startup can cause filesystem corruption and an inability to read files in shared filesystems, including in the ESP, where boot loaders are stored. Of course, if you can't boot Windows, you won't be able to disable this feature, which puts you in a conundrum. Either of the following two suggestions might help get you out of that conundrum, though....
• You could try using my rEFInd boot manager. There are USB flash drive and CD-R images on its download page, so you can try it risk-free, without installing it to your hard disk. It's possible that rEFInd will be able to launch the Windows boot loader even when GRUB can't. You could then either switch to rEFInd by installing the Debian-package version or at least use its ability to boot Windows to disable Fast Startup. Note that rEFInd is likely to show two Windows options. Try them both.
• Based on your error message, it looks like you're using the Windows Boot Manager (UEFI on /dev/sda2) GRUB option. Instead, try the Windows UEFI bkpbootmgfw.efi option; it might work better.

Your problem is probably a broken path to the Windows UEFI file. To fix this, follow these instructions.

1. Boot into Ubuntu.
2. Start up a Terminal emulator with Ctrl+Alt+T
3. Run the command, sudo update-grub
4. Reboot. Hopefully, GRUB updated it's configuration to the correct path of the Windows UEFI file.