Cannot install Windows 8.1 on MacBook Pro 13.3 Retina (OS X Yosemite) from an external DVD drive. After booting from the Windows 8.1 installation DVD and trying to install Windows on BOOTCAMP partition, following error is displayed:
Windows cannot be installed to this disk. The selected disk is of the GPT partition style.
Windows cannot be installed to this hard disk space. Windows must be installed to a partition formatted as NTFS.
Trying to format the partition doesn't help.
Boot back into Mac OS X and launch Disk Utility. Select your Windows partition and format it in ExFAT format.
Boot from Windows installation DVD again and reformat the Windows partition in NTFS format. Now Windows should install with no issues.
The issue can also be resolved by creating a bootable Windows 8.1 USB drive using Boot Camp Assistant.
OS X Yosemite (10.10)