I would have expect that the second partition would be displayed as DH1:NDOS
If you recreate the entry in the partition table exactly as it was before, then the partition will appear again as it was before. Editing the partition table does not touch the actual partitions.
When I try to format DH0 the format tool does not show up. I can't format it.
I don't undertstand what you mean by that. The Format program does not run? When you double click Sys:System/Format, it does not open? Nothing happens? What if you run it from a Shell?
format drive dh0: name Workbench noicons quick