We have a Drobo connected to a Mac running Leopard that had a kernel panic. When the machine was rebooted the drive would not mount. The drive is visible via Disk Utility, and displays an error of “Invalid Volume Header” when verification is run. It gets fixed by the repair, but still will not mount. Attempting to mount causes the error to show up again when verified. I have connected the drive to several other machines running various versions of the OS with the same results.
I am trying to scare up a copy of Disk Warrior, but is there anythign else I should be trying in the meantime?