How can I repair a hard drive that Disk Utility and Disk Warrior can't fix? I have a Mac Pro running Mac OS X Lion, and one of my hard drives has acted weird since attempting to repair permissions. I used Disk Warrior, but it says the HD can't be rebuilt. When I try to format it with Disk Utility, it takes forever to unmount.
I'm wondering if there is a surefire way to format the HD with another program or through the command line.

The HD is 2TB, and the SMART status is verified, so I doubt it is a physical issue.
Many problems can cause such a problem. SMART status is unreliable, but it's good that it's at least 'OK'.

If you don't care about data and just want to format and repartition your HDD then you can:


Check the disk for bad sectors. If it contains bad sectors it may be not a good idea to use such a disk at all. Here are some nice tools that can be used for this.
wipe the disk using dd (make sure that you wiping right drive):

dd if=/dev/zero of=[path to device] bs=1M
Partition it using Disk Utility