[AccessD] Could not update; currently locked

I have a database (Windows XP, AccessXP) where a child form (no code AT ALL)
gets the error message "Could not update; Currently locked" at the instant
that the user tries to select something in a combo.  The table that the data
is going in to is small, 5 IDs (FKs for other tables) a date, a time and a
memo which is actually a text field.  

The record selector does NOT display the locked symbol (circle with a
slash).  This database has a small number of users, perhaps 5 or 6, ALL of
them are working in this main / sub form.  It is a people table (parent
form) with a "communication" subform which records all phone calls etc to
the people in the parent form.  This is SIMPLE, nothing much there.

When the lock occurs, ALL users end up locked.  Any given user has to close
the main form and re-open And they can continue onward with whatever they
were trying to do.

I have checked service packs (SP3).  All machines are set to "locked
record".  The BE is compacted / repaired regularly and doesn't seem to help.

I am not there, and it is several hundred miles away so I am trying real
hard to not have to go there.

Has anyone seen something of this nature?  It looks like a PeopleComm record
is created by this specific combo selecting something, and at the instant
something is selected from the combo something locks up the PeopleComm
table.  It cannot be created on demand, but it happens regularly (every 15
minutes to 1/2 hour).  This form is the main working form for this group of
people, it is where they work, all evening.  It is a major frustration for
them.  I cannot see anything causing this.  There is no memo field, no lock
symbol, no id of which user is causing the lock, no nothing to work with
here.  To be honest it looks like an Access bug to me but...

Help!!!

John W. Colby
www.ColbyConsulting.com 

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