So this is a problem, that I have encountered the second time now. I am having machines here running dual-boot on Windows and Linux OS. I have managed to successfully install dual boot systems multiple times (first comes MS Windows 10, then Linux CentOS 7.3-1611). All machines are using the GPT partition style and as such they are UEFI systems (and they are all 64-bit systems). I use RUFUS to create USB installation media.
The problem is that Linux CentOS 7 basically cannot be installed because during the (manual) partitioning configuration the system does not let me have a /boot partition over the size of 1024 KiB and the system warns me, that it must be at least 200 MB. /boot/efi works just fine with 1 GB. I have enough space for everything but I don't know why this problem appears and how to deal with it. On the target machines a Windows 10 system is already installed.
When I select the /boot partition and specify it to have more space then it always resets itself back to 1024 KB. On my first time I encountered this I basically nuked the system, reinstalled Windows 10 and then I could install CentOS 7 for an unknown reason why it worked but I really don't want to nuke a perfectly healthy Windows 10 installation again.
In case you ask why I use both /boot and boot/efi on UEFI systems - that's because for some reason CentOS 7 could not be installed with boot/efi partition alone and I could install it only with both boot and boot/efi partitions. Maybe someone can enlighten me about this?
I also checked on Windows 10 the Disk Management utility and it looks like one chunk of 45 GB unallocated space is available, so the problem is unlikely to be sliced and unallocated partitions.
Picture for reference (not mine)
