Windows 10 Windows 10 keeps installing bootloader on a seperate hard drive! Why?

[treepi]

Below in my screenshot I have marked the W10 installation, W10 bootloader, and Linux install. For some reason, every time I install W10 it decides to install the bootloader on a seperate drive. When I boot into the linux drive grub shows W10 but I am unable to boot into it. I am able to boot into windows by selecting it when pressing F11 during boot up.

Anyone know how to move the bootloader to the same drive? Or how to install W10 and the bootloader on the same drive? I don't mind reinstalling as I have nothing important on here. I cannot figure this one out though. It's driving me mad!

I've tried EasyBCD to move it and I get the error saying it's not a primary partition when it is indeed one. So idk what to do. Is there a way to instruct the installer to stick to a certain disk only?

 

[nmsuk]

I'm going to presume, linux is using that EFI due it's size. The standard windows EFI partition is normally only ~100MB

 

[Neemobeer]

I believe the default used to be 500MB~ and MS changed it to 100MB as of 1709. If you do the simple install version I believe Windows decides where to put the partitions. It may have detected the GPT partition and decided to use it. I don't think the logic for the installer is really documented. When in doubt when installing Windows it's best to physically unplug all the drive except the one you wish to install on. Typically it's more convenient to have all the boot loaders on the same partition, so you don't have to select the disk to boot from each time you wish to switch OSes.