I have a front-end/back-end database that I would like to put the front-end
on about 15 users machines.  Currently the front-end is loaded on 4 machines
with the back-end on the server.  The first three people can open and the db
and add records with no problems.  When I added the 4th person, she keeps
getting a "file is in use" message.  It's not saying what file.  I have went
into both the front-end and back-end to unselect "edited record locking" and
made sure both db are set to "shared".  I don't see any record locking
options at the table level.  Also, when any of the user open front-end and go
to a specific form it throws a copy of the db out there .ldb.  I have made
sure all the users have gotten a new copy of the front-end on their desktop.  
I have made sure their all running the same runtime version with current
updates.  I'm not understanding why it works for 3 users and 4th user is
having problems.  Any help would be appreciated.