Unable to choose GUID options


macrumors 6502
Original poster
Oct 13, 2009
I have a Mac Mini and on the internal drive I have Snow Leopard installed on the first partition and I'd like to install Snow Leopard Server on the same drive on another partition (I'm new to Mac, this is my only machine and my only drive, and this is only for testing purposes, so don't bother with stupid questions about why etc).

The problem I have is that I can't seem to create the necessary partition in Disk Utility. I have shrinken the Snow Leopard partition to get some free space and I've created a second partition for Server but for some reason I can't choose the options button to select GUID. The button is grayed out, see attached image.

What am I doing wrong? Or is it not possible to have two OS partitions on the same internal drive?



macrumors 603
Jan 6, 2002
Partitions aren't GUID. Your Partition Map is GUID, which is already setup correctly (otherwise you couldn't boot the computer at all). You aren't reformatting the entire drive, thus you can't change the Partition Map. You're already done from what I see, except to apply the changes. All you need is to add the one Mac OS Extended (Journaled) partition, as you have done.

Why are you setting this up, though? I know you said not to bother asking, but keep in mind, if you're asking simple questions like this (not stupid, just basic), you're going to struggle understanding the server. If your purpose is to learn, all the more power to you, and make sure you've got a good book or something. If not, then I would make that your purpose first.



Staff member
May 3, 2009
Selecting partition type is done when you have the drive (not the partition) highlighted and because you already have your drive setup for OSX, the type will already be GUID.

Create a new partition in drive utility and you'll be able to install OSX server on it if you wish.


macrumors 6502
Original poster
Oct 13, 2009
Thanks for the fast reply guys :)

Well, I've had this Mac for one week and I'm completely new to it, can't know everything from the start. I come from the Windows world since many years back and things don't work the same way over there. I read somewhere that the "partition" has to be GUID in order to install an OS on it, that's the reason for my stupid question about the grayed out button :p

Is there a way to install/boot the Server without dvd disc? I don't have a disc yet, only a DMG file.

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