[SOLVED] Need Dual-boot on Mac Mini (late 2012)

[anubisX]

Here is the situation :

I want to install Windows 10 on my Mac Mini.
I have Windows 10 64-bit/32-bit ISO but Boot Camp Assistant won't recognize the 64-bit.
Copied the content of ISO in the USB stick and also copied the Boot Camp drivers for Windows in the USB stick.
Created a partition from Disk Utility in FAT.
Tried to boot from the USB stick, Windows 10 start up came, tried to install on the disk but got an error " Windows cannot be installed on this disk. The selected disk has an MBR partition table. On EFI systems, Windows can only be installed on GPT disks."

Tried deleting, formatting, making that new disk but to no avail.

All suggestions will be welcomed.

 

[anubisX]

That problem got solved. Just deleted that partition from Disk Utility and left it as Free Space. Then rebooted to the USB stick and created a disk with that unallocated free space and Windows created 2 partitions. One is like 16MB system reserved and another with remaining. Windows installation started and went through, a restart or two and Windows 10 is up. Need a wired keyboard-mouse to install the BootCamp drivers as bluetooth keyboard-mouse is having some problem.

New problem, when I restart the Mac Mini, it goes straight to Windows instead of OS X. The ALT/OPT key isn't working like it used to. Is the OS X gone or it's just the Windows is preferred OS now ? How do I get the option back for dual-boot ?