Cannot install Win 8 on a late 2013 iMac using bootcamp on 10.9

Question

I'm trying to install Win 8 on a late 2013 iMac (purchased a couple of months ago)
I have a win 8 pro DVD, but obviously there is no DVD in this iMac. I usally use the DVD drive in my older 2009 iMac for any disk based installs but I can't appear to use it here.
I followed the instructions and downloaded a Win 8 Pro ISO from Microsoft to use with my authentication code, created a bootable USB using bootcamp, created the partition and rebooted. Once I'd entered the code I get to the install location but it says I cannot install on the partition created by bootcamp. Even if I format the partition it says I need a GPT drive but I have MBR, so won't let me install.
I tried several suggestions including creating aprtitions in various other programs and once I even got past that screen, but as soon as it tried to install I got another error saying the MBR was formatted incorrectly and it failed.
I had no issues installing Win 7 via bootcamp on the older iMac, but this one has me stumped. I used to think I knew a bit about computers, but I'm fairly new to Mac related issues as the older iMac has always just worked.
Any help would be greatly appreciated.

Answer 1

Hello,
I just installed Windows 8.1 on my Late 2013.
There are just a couple of things I had to do that deviated from the Boot Camp Installation Manual.
1.  I downloaded my copy of Windows 8.1 as an ISO image AND as a bootable USB from the Microsoft site.
Not sure why I did that but it came in handy because Bootcamp was taking a very long time to copy the ISO onto the USB stick..
The ISO copying seemed to freeze up, but it's likely that it was just taking a long time, probably 20mins.
So, instead of waiting, I took the contents of the the USB startup stick and simply moved them over to the stick that Bootcamp had formatted for the ISO copy (I cancelled that copy function and deleted any files that had copied but didnt complete).
Once that was done, the machine rebooted from the USB stick and began the normal Windows setup process.
All went very smoothly except that my mouse was not working.
2.     To get around the mouse issue, I simply plugged in a MS USB Mouse and it worked immediately.
The Bootcamp manual advised that the way around this was to 'click in upper right corner and search for Bootcamp'.   Problem was, it was nowhere to be found.
So, using my MS mouse, I navigated to the 'DESKTOP' icon in Win 8.1 and found File Explorer, which showed my USB stick connected along with Bootcamp and the MS Support File (i.e. All the Apple Drivers).
I began manually clicking on all the driver files until realizing that there IS a Bootcamp executable which will automatically install the drivers for the Nvidia card, keyboard, camera, mouse, etc....
Once that was done, my installation was completed.
The entire process took about an hour, but now that I've done it, it really shouldnt take much more than 45 mins.
I have the late 2013 iMAC, with the GTX780M and 1TB Fusion Drive i5 Quad Core.
For those who are leery about doing this, please note that I'm a PC 'lifer' and this is my very first go-around with doing anything on an Apple product.
It all went much more smoothly than I could have imagined, but if you are not a PC person, you might be a little challenged finding the Bootcamp in File Explorer or doing anything in Win 8.1 to get over these minor hurdles.
Good luck!
I'm looking forward to getting STEAM up and running to see how this thing games!