Missing Operating System when Installing from USB

Question

I cannot for the life of me get ubuntu to install on my macbook pro. 5,2...I am trying to install via these instructions.

https://help.ubuntu.com/community/MacBookPro5-1_5-2/Natty

I have rEFIt working, and I successfully synced my partitions, but when I got to the linux installer drive it just says "missing operating system". What am I missing.

EDIT:

Created new question for what I think the problem really is Grub will not install correctly with EFI on my Macbook Pro

Answer 1

Those instructions are six years old, and things have changed a lot in the intervening years. Most importantly:

• You refer to syncing your partitions. I assume you mean using gptsync or a similar tool to create a hybrid MBR. This is necessary to boot in BIOS/CSM/legacy mode on a Mac, but both a hybrid MBR and BIOS-mode booting are ill-advised today. You're much better off installing in EFI mode, which requires no hybrid MBR. (Hybrid MBRs are ugly and dangerous; see the page to which I just linked for details.)
• You refer to rEFIt, which has been abandoned since 2010. I forked rEFInd from rEFIt in 2012, and I'm still actively developing it. Thus, you're much less likely to run into problems with rEFInd than with rEFIt, particularly if you're using a relatively recent version of OS X/macOS, which add features that will stop rEFIt from working unless you know how to work around them. (These features do affect rEFInd, but at least they're documented in rEFInd, and in some cases the rEFInd installation script automatically compensates.)
• Ubuntu has moved on and provided better support for Macs in the six years since Ubuntu 11.04 was released. I strongly advise against installing Ubuntu 11.04 -- it's no longer supported, so you won't get important security updates for it, and in fact you'll be out of date the moment it's installed. Instead, I recommend using the latest Ubuntu LTS point-release (16.04.2 as I write) or perhaps the latest non-LTS release (17.04 as I write). These versions will be likely to install better on your Mac, particularly in EFI mode, than a six-year-old version.

I don't have a reference to step-by-step instructions for your specific computer; but the following guides to installing on EFI-based computers generally may be helpful:

• My page on installing Linux on EFI systems -- This page is a practical introduction to EFI-mode booting.
• My page on the CSM -- This page covers the CSM, including when it's useful and when it's not.
• The Ubuntu community wiki entry on UEFI -- This page is a bit disjointed, but is the most Ubuntu-specific introduction to EFI and its issues.

If you install Ubuntu in EFI mode following "generic" EFI-mode installation instructions, which are usually written with UEFI-based PCs and dual-booting with Windows in mind, GRUB might take over as the boot loader, and the computer might or might not successfully boot to OS X from GRUB. If you can boot to OS X from GRUB, and if this is acceptable, then fine; but if not, you can probably work around the problem with rEFInd on a CD-R or USB flash drive. You can then install rEFInd in OS X -- or even in Ubuntu, if you have problems getting the removable medium to boot. (I generally recommend installing rEFInd in OS X rather than in Linux because Macs are weird; but for the past two or three years, installing in Linux has generally seemed to work OK.)