[AccessD] Error 70 - Permission Denied

Dear List:
 
I have a user using an app compiled in A2K3, using run-time from
Wise/Sagekey.  Back end is on the server, front end with run-time is
installed on each client.
 
All clients have been running fine.  One does not - many operations in the
app generate an error 70 - Permission denied.  The error is trapped by my
error trapping and a message box is displayed with options to email or fax
the error to me.  Then the app closes and must be restarted.  
 
An oversight - I left the control box on the message so the user has just
been minimizing the error box and carrying on (gotta fix that toot sweet).
The user finds that the transactions she was doing when the error is raised
are all complete and correct.  
 
They can't tell me exactly how long this has been going on or what might
have changed right before this problem started.  
 
I had them copy the back end to the client and relink the tables locally to
see if it was a problem on the server.  Still had the problem.  
 
Then I had them relink the tables to a local demo database to see if the
problem was in their back end.  Same problem.
 
All clients are running the same version of the app.
 
So I think I've eliminated the back end, the front end, and the server as
problems.  It would perhaps seem to be a question of the user account.  But
I really don't know where to look.
 
Any guidance on what might be causing the problem and where to begin
looking?
 
MTIA
 
Rocky Smolin
Beach Access Software
858-259-4334
www.bchacc.com <http://www.bchacc.com/> 
www.e-z-mrp.com <http://www.e-z-mrp.com/> 
Skype: rocky.smolin