Office - Error Code: 0XE0000203 - cache corrupted?

I get the following message in one notebook of ON:  OneNote cannot
access the notebook cache file.  It may be corrupted.

The message continues by saying it will delete the cache and restart
again.  This happens in the same notebook repeatedly -- so deleting the
cache and creating a fresh one is NOT curing the issue.

I have tried the 'optimize all files now', but this has not changed
the result.

I'd appreciate suggestions.

David

Are you running 2007 or the 2010 beta?

ON 2010 beta (on WinXP(SP3)).

The notebook was created in ON07 and converted to ON10 Beta.

However, I converted other ON07 notebooks to ON10 Beta -- and they
work fine.