Unable to delete or re-partition internal drive using Disk Utility

Question

When using Disk Utility, after booting onto the recovery partition, I can't...

• Re-partition
• Delete partitions
• Repair partitions

Answer 1

There are limits to how much you can do with your hard drive when you've booted the recovery partition. Even though the recovery partition is a separate partition, it still locks your drive to some extend, and prevents you from doing "live edits" - primarily modifying the partition table.

Instead of holding down the ALT key, and booting onto the recovery partition; hold down COMMAND + SHIFT + R -- doing this will download the utilities package from the Internet, and put it in memory. This "unlocks" your hard drive, and let's you re-partition it.