After installing Ubuntu 12.04 I used Ubuntu Boot Repair (as usual) to reinstall the GRUB and visualize the other OS installed (ie. Windows 8). Unfortunately,this time something didn't work at all, and I am now not able to boot into Windows 8, which soon after selection in the GRUB starts and fails the Automatic Repair.
Even OS repristinating doesn't seem to work. I think I have installed the Ubuntu 12.04 boot loader in the same partition of the Win8 boot loader (sda2, EFI), so, as a results, Ubuntu boots perfectly, while Win8 doesn't. Is there a way to rescue Windows 8 without reinstalling it? Step by Step advice will be welcomed! XD