old e-mail about dual booting woes
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Authored by demon on Dec 3 2014, 5:24 PM.

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	Hey <snip>,

	You're a Mac guy, and are generally tech savvy in things I am not, and I am
	faced with a mild conundrum. This is super low priority and is something I'm
	only trying to resolve in my spare time anyway, so don't feel any urgent need
	to answer this before you have a chance. I thank you in advance for any
	advice you can give by the way.

	Backstory: I have an Intel iMac running Leopard on an SATA drive. About 2
	years ago, I decided to dual-boot Ubuntu and OSX off that same drive. In the
	process of doing so, I converted my GPT -> MBR (I was having some
	difficulties in getting Ubuntu to work off the GPT). I ended up using rEFIt
	instead of Grub since it played nicer with OSX's HFS+ partition. I have since
	gotten rid of the Ubuntu install and given its space back to OSX's HFS+
	partition.

	I want to upgrade OSX to Snow Leopard on this box, but every time I try--
	either through the Launcher or booting to the upgrade disc--it won't let me
	because "Mac OS X cannot be installed on Macintosh HD, because this disk
	cannot be used to start up your computer." From Googling around, I quickly
	determined this was because OSX cannot be installed unless GPT is being
	used--despite the fact that OSX will boot from a MBR just fine.

	So began my saga of attempting to rid myself of my MBR. I eventually found
	that gdisk will do this for me. After some wrangling there[0], I managed to
	convert my MBR back into a legitimate GPT without wiping my disk \o/
	Attempted to install Snow Leopard again, same failure. I then found that the
	MBR that GPT keeps in a separate sector for back-compat reasons was out
	of sync. According to [1], this could also be causing my problem. I came across
	gptsync, which very easily re-sync'd the two boot formats. Still no luck on
	installing. The current output of my partition info (gptsync & fdisk -d) is [2].

	I am at a complete loss at this point, and anything you can point me to would
	help. I'd really really like to not wipe the disk if I can avoid it (I've gotten this far
	with all my data intact). If you have no f'ing clue, that's ok too! Feel free to pass
	me off if you can think of someone who knows.

	Thanks!!

	-Chad


	[0] http://www.rodsbooks.com/gdisk/mbr2gpt.html
	[1] http://reviews.cnet.com/8301-13727_7-10330520-263.html
	[2] http://p.defau.lt/?G1ePYx4u2KjlKQW04ny_Xw