I need to reformat my Mac OS X partition for a clean install and when I boot into the recovery partition to do so I am unable to erase the partition. Some times in disk utility it shows as greyed out (unmounted) and will not allow me to mount. Then other times it will show mounted and I will be unable to unmount and erase. Any body dealt with this before. Help is much appreciated.
J
Mac OS X (10.7.3)
I've not read of anyone else having this problem.
Do you have another partition, such as a Snow Leopard partition. If so, try Disk Utility from there.
If you have disks that came with your computer or a Snow Leopard disc, trying booting from the disc and trying Disk Utility from there.
I've not read of anyone else having this problem.
Do you have another partition, such as a Snow Leopard partition. If so, try Disk Utility from there.
If you have disks that came with your computer or a Snow Leopard disc, trying booting from the disc and trying Disk Utility from there.
Yeah, when I bought the machine it was SL and it's now upgraded through until mountain lion so I will try the disk for SL and see how that goes!
Thanks for the suggestion!
You're welcome. I'd erase the entire disk if possible so when you reinstall, you get a new Recovery Partition, since something isn't right.
Hi,
So I tried to reformat with the SL disk in and I was given the error. This operation requires an umounted disk. Now the Disk is mounted but the Mac OS X partition that I want to erase is mounted I think. Is the way around that to unmount the entire disk and then try erase the partiton? I have a Bootcamp partition with a lot of university work and programming programs etc so I would really like to avoid an entire disk reformat.
Thanks again,
J
I've never used Bootcamp but the TroubleShooting section of this link (If You Can't Partition Your Disk) might help.
You might want to consider making a bootable USB/DVD disk in case you have future problems.
You can make a bootable USB/DVD with Mountain Lion with this program: Lion Disk Maker
Unable to reformat my boot partition when booted into recovery
