Troubleshooting bootloader on dual openSUSE / Windows 10 system

Hi all! I’ve been gone from Linux for a long time now, but I’m trying to come back to the distro that feels like home to me: openSUSE. I have a computer which came with Windows 8.1 preinstalled, and I have since upgraded to Windows 10. I have disabled secure booting, and was able to install openSUSE to a partition with no trouble. I mounted the Windows EFI partition to /boot/efi, and after the installation, I was greeted with the openSUSE bootloader giving me the option to boot to openSUSE or to Windows. Both options load the correct operating system. However, if I choose to boot to Windows, the next time I restart my system the bootloader has changed. The only options listed are to start a new openSUSE installation, or to go to openSUSE recovery. Please help me to figure out how to get these two to live in relative harmony!

You may want to try this, it has worked for me when I had Windows 8.1 and now with Windows 10.

I have an HP desktop (UEFI) with Windows 10 installed and what I did was to create a new EFI partition for Opensuse to use. I let Windows keep it’s own EFI partition (labelled as sda2) and installed Opensuse 42.1 using the new EFI partition I created (labelled as sda5). At first it kept defaulting to the Windows efi partition (sda2) until I clicked on Rescan Devices at the bottom of the screen. After that it showed me the new partition setup with Opensuse using sda5 as its own boot/efi partition. I can now boot up into Opensuse or select Win 10 from the boot menu.

Thanks for the help! I figured it out last night.

Every time Windows reboots, it tries to set its own bootloader as default again. To fix this, execute one of these commands from an elevated command prompt:

If using secure boot:

bcdedit /set {bootmgr} path \EFI\opensuse\shim.efi

If not using secure boot:

bcdedit /set {bootmgr} path \EFI\opensuse\grubx64.efi

Thanks for all the help!