Hello everyone. I know there is very complex debate online about those issues with second hard drive in a macbook's and even to the point of needing to edit plist file in the bootcamp app itself. So to make things clear for everyone how to deal with this issue I'll let you know how I finally found a way around it What i have is: MacBook Pro Late 2011 17" with i7 CPU 2860Qm and I have removed DVD drive and mounted caddy to place my main 750HD into this one and Putting Samsung 840Pro as my main system Drive. Prerequisites: Tuxera NTFS Parallels Windows 8.1 iso image. USB Caddy for Hard Drives WinToUSB Idea: Installing Windows 8.1 on the second drive(750GB) partitioned in this way: 1st partition 250GB NTFS (Name: Win81) 2nd partition 500GB NTFS (Name DATA) 1. Remove hard drive from MacBook 2. Put it into USB Caddy 3. On Windows computer (or Parallesl runing Windows) reformat The drive acordingly to what you have planned (250GB+500GB) all NTFS 4.Next download WinTOUSB and follow the instructions of the program to dump windows iso file into the 250GB partition on the hard drive you have just formatted. 5. Put the hard drive back into MacBook 6. Boot with option key pressed and select Windows Partition1 to boot. 7. Install Windows 8.1 + Bootcamp Drivers 8. Enjoy having fully working Windows 8.1 Hope that helps. If you will have any problems with this PM me and I'll try to help. PS. If something is not clear in this steps please let me know and I'll edit this to make it more clear.