Just documenting the behaviour of Gparted that I have seen many times, with no logical explanation for a new MBR not being written correctly(?) or not overwriting a prior GRUB MBR correctly (?) so not leading to correct booting, with some hard drives but not others.
Normally you write a new partition table for a Windows install (especially if you had linux on the disk) if you want to copy install files from a Win.iso to then boot and install, from the Device menu of Gparted.
Sometimes this fails to work as the WIn files are not booted into so hangs, and I found that using command line fdisk to create a new empty DOS partition first, then rebooting solves the issue.
sudo fdisk /dev/sda
You can then use Garted to do the other ops like partition, format and set a boot flag, before copying the Win install files to the drive and booting into it.
See the original Post here: