09-17-2012 06:20 AM - edited 09-17-2012 06:57 AM
There are two solutions for your problem.
WARNING! Both the ways that I suggest will ERASE ALL OF YOUR DATA ON YOUR HD! If you have anything you want to save, copy it before doing it.
First, easy, is to erase all partitions from your disk via windows installation utility. Then, windows will offer you to convert disk to GPT.
Or, if windows doesn't do it in this 'automatic' way, you can convert disk to GPT using diskpart.
For this, use this manual to access console http://www.sevenforums.com/tutorials/682-command-prompt-startup.html
Then, type following commands
Wait until it loads, and then
LIST DISK <-- this will list currently connected disks, you should determine which of the disks is the one on which you want to install windows and remember its number.
SELECT DISK <0> <--you should replace <0> with the number you had on previous stage, in most cases, it would be 0
CREATE PARTITION EFI SIZE=200 OFFSET=1024
SELECT PARTITION 1
FORMAT FS=FAT32 QUICK
CREATE PARTITION PRIMARY SIZE=<size_for_win_partition_in_megabytes> OFFSET=206848
SELECT PARTITION 2
FORMAT FS=NTFS QUICK
That should be all) After this, you should be able to install windows on your hard drive.