Bootcamp broken after adding 3rd partition

Question

I've broken Bootcamp after foolishly attempting to add another partition on Lion (to install Snow Leopard, to run Quicken 2007). Now I can't boot into Windows. Interestingly, I can access it via Parallels, but there are times I need to be in native mode. Any ideas on how to fix it? I tried booting off the Windows 7 install CD, but when I get to the repair screen, it gives me an error that the system isn't the right version to repair. Odd, in that it's the system that was installed off that very disk, though it has been updated via patches over the last year.
Any help in a way to not have to reinstall everything?
Thanks!

Answer 1

Added a partition how? Disk Utility doesn't let you do this. Although the command line utility 'diskutil' will let you split partitions. I don't know if it properly writes out a new hybrid MBR however. Apple hardware is EFI firmware based, and EFI and Apple's OS installer want a GPT disk. But the CSM-BIOS that Apple uses for Windows support isn't activated unless there's an MBR. So there is a very non-standard and fragile thing called a hybrid MBR which is what Bootcamp creates to support Windows. Chances are, by adding a new partition, it was added to the GPT causing a new GPT and protective MBR to be created, wiping out the hybrid MBR. It is possible to fix this without reinstalling anything (assuming you haven't corrupted any partitions indvertently which is possible with hybrid MBRs), and for free.
In terminal, type this command, post the results:
diskutil list
This will list all disks and partitions for those disks, from the GPT. Chances are the disk you're interested in is disk0, which I will assume in the next command:
sudo fdisk /dev/disk0
This command will list the partitions for disk0, from the MBR.
Once I know what that looks like, I'd have a better idea of the state of the disk. The next step involves getting GPT Fdisk (also called gdisk) from here:
http://sourceforge.net/projects/gptfdisk/
This can be used to create a new hybrid MBR and set the active (boot) flag on the proper MBR partition for Windows. It is a command line utility, the options to choose are not obvious for most people, you can easily get into big trouble quickly. So make sure you have a backup, go really slow, and ask for help. If you don't get it on the Apple forums, you can generally find knowlegable people about MBR and GPT, and dual booting situations on the Fedora Forum in the Mac forum.
http://forums.fedoraforum.org/forumdisplay.php?f=51