Hi I have a machine with Ubuntu 12.04 installed. The machine came without an os on it so I installed Ubuntu. I now would like to install windows which in the past I've had a windows machine and then installed Ubuntu with no problem, however, I haven't found much for doing the opposite.

What Ive done so far is install gparted which i used to format my external hdd and put a ntfs partition on it. Then using UNetbootin I wrote my iso to my hdd after following the instructions in the following link. http://www.webupd8.org/2010/10/creat...usb-drive.html

I've tried winusb and the tool microsoft provides for creating a bootable usb hdd which was windows only which i ran in a vm however even though the vm showed my external hdd in computer on windows none of the programs would recognize the usb external hdd.

Anyway what I now need to know is how I can partition my computers hdd in ubuntu and preserve my data in Ubuntu, and then I know to press f7 as my computer is booting up and run the windows setup.

I just need to know mainly how I can partition my drive without losing data as well as if there is anything else i need to worry about. For instance, I've read I'll need to reinstall grub which I don't know much about so any help on what i should do from here would be greatly appreciated so I don't lose any data or mess anything up