I installed Ubuntu 18.04 on my Mac mini (late2014) and when it boots, it goes directly into Ubuntu. However, it won't load. An error message states the following:
failed to open \EFI\ubuntu\grubx64.efi - not found failed to load image \EFI\ubuntu\grubx64.efi: not found start_image() returned Not Found
I know for a fact that I haven't overwritten my partition of the Mac OS (I was very careful about this and double checked everything) but I didn't load rEFind in the Mac OS side before doing this. I have tried using the Apple commands such as option, command+r, and command+option+O+F to bring up the UEFI or other menus with no success and I keep getting returned to the screen error above. I have tried an Ubuntu live boot on USB and booting with a bootable USB containing rEFind iso and still get returned to this error screen.
I do not have a keyboard that has a USB connection port (all my stuff is Bluetooth) and I will try this tomorrow because I found somewhere that the new Mac minis don't load the Bluetooth keyboards until the kernel is loaded which may explain why I can't open the UEFI.
what I am looking for is any additional help that might solve the problem. I currently can't get into either OS or reinstall either of them. I really would like to get into using Linux, but I don't want to give up my Mac OS either. Please help!