Sometimes, 'Names' becomes corrupted. I have experienced a situation where the Notes field in Names could not be opened for editing any more (error message: 'Sorry, a problem has occurred. (View missing viewClass)'). With the help of an NTLK list member I managed to fix my names soup by exporting-deleting-importing it (not backup-restoring).

But first:
"It is always best to try fixing it first via SBM, Name fixer, soup moving, etc. before you try exporting via NCU. The reason is sometimes a soup gets so corrupted, exporting may not work. Although when it gets this bad, usually Names won't open."

I connect to my Mac via wireless. Exporting-deleting-importing results, in the deleting step, in the removal of some information necessary for successful wireless connection. That will be of no concern for those using serial/cable connection. I don't know whether any ethernet-settings are stored in the Names soup that you might want to look up and save somewhere before the deletion step.... (to be edited by knowledgeable ethernet users)

First do a backup of Names, to a card, or via NCU to your Mac/PC for keeping the information in-spite-of-the-problem you might have

1. Export (text delimited) all Names via NCU

If relevant, copy WEP hex key from the wireless Card Setup to notes....

2. Remove Names soup with soupKitchen.

Everything (dock, wireless card setup, owner) now complains - must be lost owner connection

3. Reset Newton (owner now OK, wireless card setup accessible)
4. Fill in WEP stuff on card setup if applicable, 'cause it has disappeared...
5. Connect to NCU
6. Import the text delimited Names file to Names (through two dialog boxes)

7. Look, with great satisfaction, at a number of names (after changing things to show all Names(!))
8. Tap Notes in a Name Card previously frozen with the viewClass complaint: it opens up for editing!

Then:
"Also after all of this, make sure you keep that old backup from before the fix for a while. I doubt you will need it, but if you find one important name missing somehow (again I really doubt it but better to be safe than sorry) you can backup, restore the old version with the error to get the name info, then restore your fixed version and add the missing name in question."