I had similar problem recently.
Basically the drive I was using would not unlock via xboxhdm23usb so I did the hotswap which I was able to unlock. Then once it was unlocked I ran into the same issue you got. It seems like it is formatted but it wasn't.
Once I changed to another IDE -USB adapter it worked correctly.
Thanks for the great instructions. I can't seem to delete a file or copy a file once in Xbrowser? I want to try deleting the broken xboxdash and trying a good one.
Hi All
My Softmod with larger Hard Drive installed could not find the original Xbox Dash to boot into.
I tried a Slayers Disk to restore this however now every time I boot I get an Error 21.
Before I replace the original Drive back in and redo everything is there anything I can try to fix this?
Many Thanks