I've searched through here and have tried to fix this issue but nothing seems to work. I recently installed Ubuntu on my HP PC that came with Windows 8 pre-installed via UEFI. I'm new to Ubuntu and Linux all together but I would really like to learn. So during the installation I chose to "Install Alongside Windows." After completing the installation the option to choose Windows 8 would not work. I had to have use System Setup and go into the boot options and Select Windows Boot Loader. So I searched and saw that I should run boot-repair and so I did. Well after that it added numerous other options in Grub. I can choose Windows Boot UEFI and it will load windows. Now, though when I select Ubuntu it won't boot. It just stays on a blank purple screen. I can only boot into Ubuntu if I have the LiveUSB plugged in. What should I do? I just want to be able to choose between Windows and Ubuntu and they both work. Here's this if it helps..
Leave secure boot on, and avoid the non-UEFI Windows boot grub entries. Those have the wrong chainloader +1 command instead of an EFI Path. You could try to clean them up by editing the files in /etc/grub.d, but that's not really necessary. Append a good UEFI Windows entry from the grub.cfg file into /etc/grub.d/40_custom, and edit the 30_os-prober to remove the Windows entry (or just remove the permission bit from the 30_os-prober to make all the entries created by it not appear). Then run
to update the grub.cfg file and the grub menu. Of course, you could just edit the /boot/grub/grub.cfg file directly, but the changes will get overwritten at the next kernel update.