Unable to find device node…

I am trying to install FreeBSD 8.0 on a hard drive that used to have FreeNAS installed on it. Unfortunately, when I got to the part of sysinstall where it starts formatting the drives, I get the following error:

Unable to find device node for /dev/ad6s1b in /dev/ad6! Creation of filesystem will be aborted.

Did some Google searches and found the fix was to overwrite the MBR with dd if=/dev/zero of=/dev/ad6 bs=512 count=1 and various combinations of the dd command. I tried it every way from Sunday with no flippin' luck. I was getting really pissed. I even tried installing another Linux distro but I had other issues there.

Finally found a fix - Run Darik's Boot and Nuke (aka DBAN)!!

I let it overwrite about 1% of the disk, rebooted and started in the install again. Now things are working great.