High Sierra being a newer OS is not as backward compatible as Lion.Īfter the dual boot system was setup, I upgraded Lion to High Sierra without causing any problems for Windows since the update didn't reformat the disk and thus still the same system partition prepared by Lion. Not just installing Lion over a disk partitioned by High Sierra, but have Lion format the disk too.Īlthough Lion prepared a GPT disk just like High Sierra, it is obviously that the two GPT disks are NOT exactly the same! A GPT disk formatted by Lion is compatible with a Windows' MBR partition! My anecdotal observation is that with Lion as a circa 2011 OS, it is more compatible with the legacy BIOS mode. This suggests we cannot have a dual boot system of Windows 10 and High Sierra on this particular Mac!Īfter trying many alternatives, eventually I got it to work!!! Instead of installing High Sierra first, I got it to work by installing Lion first. The selected disk is of the GPT partition style.' If I wiped the disk clean and installed High Sierra first, then the Windows installer would complain 'Windows cannot be installed to this disk.

It appeared when Windows was installed in the legacy BIOS mode, it formatted the disk to MBR, but macOS was expecting GPT.

If I started out with a blank HDD/SSD and installed Windows first in the legacy BIOS mode, when it came time to install High Sierra, the installation would complain 'Couldn't modify partition map'. Officially Apple does NOT support Windows 10 on this Mac. Windows 10 must be installed in the legacy BIOS mode for all functions to work on a Macbook Pro Late 2011. After days of effort pursuing this problem, here is my solution. I tried the Cirrus Logic fix to no avail.

Imac 2011 cirrus logic sound driver