I had windows and ubuntu installed in dual booting for the last three years and everything was going well until today. Usually the screen would come up for me to choose whether to go to ubuntu or windows.
However today I encountered GNU GRUB "Minimal BASH-like editing is supported". I started by looking through my partitions and could only access one (others are "unknown filesystem). In there I have two folders: efi/ and boot/, but nothing else. I was able to find the grub.cfg file but nowhere vmlinuz, linux-3.2.0-14*, etc.
Thus I could not do anything that https://help.ubuntu.com/community/Grub2/Troubleshooting suggests. I was able to get into my windows and tried to access my linux files using DiskInternals Linux Reader, but it did not let me open those partitions. I tried live booting from a usb, and reinstalling, which did not work either (just a black screen after choosing those options).
My last try was using boot-repair disk, which booted and repaired, but rebooting my computer I still end up at the same GRUB screen (so the problem was not repaired). I would be very thankful for any further advice!