Never mind.
I removed the drive from the 722 and hooked it up to my Windows machine. The settings file was corrupted and apparently the 722 was locking up when loading. I reformatted the drive in Windows, ran check disc, no bad sectors etc. Then I put the drive back in the 722 which of course no longer recognized it, the 722 prompted me to format it, formatted it in the 722 and everything is back to working order now.
Whew. What a relief.