HELP! Wrote over Startup Disk and now can't reset partition to be GUID

[suzie]

I installed Boot Camp on my new intel mac and then created a partition as shown to install my XP onto. I then followed the instructions but stopped short when I got to the product key part as I couldn't find it! As a school teacher, I am allowed to install the software from school onto my home computer so got a different copy of XP from there and put it into the computer. I then booted off the disk (I think this is where I made my BIG mistake) and then installed XP - it asked me which partition I wanted to install onto and only showed ONE partition (which was C). As this was the name of the partition that I was told to use when I was originally putting on XP, I selected it. It then wrote over it but kept looping back into restarting and installing again. I started up the computer again holding down the option key and there were NO startup disks to choose from. That's when I realised I had managed to overwrite my Mac startup disk. After stressing out for awhile, I got my work computer out and went hunting on the web for information. I then found info about using Disk Utility to revert the computer back to one partition but OSX still wouldn't install on this new volume. I then tried to erase the disk in order to get it to revert back to GUID partition scheme but it still kept it as a Apple HFS scheme (there was no option button to choose GUID). I am now officially out of ideas.

[John the Geek]

I installed Boot Camp on my new intel mac and then created a partition as shown to install my XP onto. I then followed the instructions but stopped short when I got to the product key part as I couldn't find it! As a school teacher, I am allowed to install the software from school onto my home computer so got a different copy of XP from there and put it into the computer. I then booted off the disk (I think this is where I made my BIG mistake) and then installed XP - it asked me which partition I wanted to install onto and only showed ONE partition (which was C). As this was the name of the partition that I was told to use when I was originally putting on XP, I selected it. It then wrote over it but kept looping back into restarting and installing again. I started up the computer again holding down the option key and there were NO startup disks to choose from. That's when I realised I had managed to overwrite my Mac startup disk. After stressing out for awhile, I got my work computer out and went hunting on the web for information. I then found info about using Disk Utility to revert the computer back to one partition but OSX still wouldn't install on this new volume. I then tried to erase the disk in order to get it to revert back to GUID partition scheme but it still kept it as a Apple HFS scheme (there was no option button to choose GUID). I am now officially out of ideas.

 

 

Easy to fix.

 

You've discovered a glitch in Apple's Disk Utility app. When you boot from the DVD to reinstall, and you erase your disk using "Partition", it will retain the existing partition (which is not GPT) and not be bootable (or installable)

 

Instead use the "Erase" tab to erase your disk. This will restore the partition table to GPT and allow you to install OS X again.

 

=)