well, i,again like hughparker1, i'm not an expert have the same problem with my laptop, a lenovo G480, with W10 (i hate W10), i installed the linux lite from a sd card-usb connector (i got the .iso in a sd because i don't have pendrives), i can use only on live mode, later i was searching on forums, and maybe your computer is blocked to install other OS partitions, i discovered that and when i turn the laptop, pressing recovery key, (in your computer maybe is the F9 or F10) i disabled the secure boot and change uefi boot legacy only to usb first, then restart with the sd-usb, started with the live mode, i installed creating a partition of 200Gb, later i restart again and the GRUB was working with the 2 OS working perfectly,maybe i can help you or not, but i was whit the same problem, better ask to [member=2]Jerry[/member] he can help you better than me.
sorry by my too basic english, i need more practice, i'm learning with this OS and this forums.
sorry by my too basic english, i need more practice, i'm learning with this OS and this forums.
thank you 