uMBP 17'

macrumors newbie
Original poster
May 24, 2009

I'm trying to install Windows 7 on my Mac without using Bootcamp as my internal drive has already been partitioned and it's really inconvenient to recombine the partitions (see setup below). I understand that Windows 7 x64 supports EFI and GPT (in theory), and therefore tried booting off it directly. Problem is, of course, that it only works if the disk boots using EFI - a normal boot (BIOS) refuses to install on a GPT partition.

Therein lies my problem: I looked through my 7 install disk and didn't find any efis! Is there any way I can add these files back in (I have an iso of the disc)? Or is there any kind of workaround for my situation? I've been goggling for 2 days now and am really desperate for a solution. Perhaps I'm looking into the wrong direction so can anyone please enlighten me?? Thanks in advance.

Setup: MBP 2011 17', Wintec FileMate 96GB (boot), Hitachi 500GB 7200rpm (Time Machine, Home folder, data), Lion 10.7.1


macrumors newbie
Apr 26, 2011
New Jersey
easy as 1 2 3

if you have a windows 7 computer, create a windows 7 boot cd. with an ISO image
step 2 start up your mac holding the option key
step 3 click RECOVERY HD
step 4 press the apple logo
step 5 restart mac
step 6 hold option key again when booting again
step 7 click windows
step 8 enjoy


macrumors newbie
Jan 13, 2012
Here's your fix

I ran into the same thing.

First, follow the directions here:

When you get to the disk/volume/partition screen on the Windows 7 installer, you need to hit Shift-F10 to get a command prompt. Type in diskpart.

All of these should not have the quotes when you type them:

1. Type "list disk"
2. Type "select disk n" (where n is the number of the disk - probably 0 - no parens)
3. Type "clean"
4. Type "convert mbr"

Now go back to your installer, refresh the screen, create your partitions, whatever you need to do and install your OS.

You can't convert the disk from GPT to MBR if it isn't cleaned first. That's where I was getting hung up. Good luck.
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