OK, just some thoughts. I throw them over to You and maybe one of them accidentaly hits the target


I'm not sure, I can do with this "Live" version and we never were able
to reproduce this problem on Development ...

Is the database on the live-system OK? Indices no corrupt indices?

Sometimes the error message pops up immediatelly after they click on the textbox in the grid

Is it the AfterRowColChange-Event? if so, Do You get the error at the "replace..." or the
".RequeryGridSources()"

I don't know if this is still valid (and if this would make a differnece at all) but I rember
"Lockscreen" to be kind of additive. In some cases You will have two .Lockscreen=.T. in a row
but only one .Lockscreen=.F.

Maybe You can put the lockscreen-pair one level down (underneath the if this.nCurRec<>m.lnRecno) so that they do not fire if you simply change columns.

You are moving the record-Pointer within the AfterRowColChange, I'm not sure if this is not causing
another AfterRowColChange

Are You sure, You're not addressing a record in another datasession?

Did You try something like this

    if ! LockR()
      wait window "Oooops..."
    else
      replace (.AddrField) with '6', ModiType with 'C'
      unlock 
    endif 

where lockR is a construction like that

PROCEDURE LockR
lparameters    tc_Alias
LOCAL ln_WasRepro, ln_INKey

ln_WasRepro = set("REPROCESS")
tc_Alias    = iif(empty(tc_Alias), alias(), tc_Alias)

set REPROCESS to 1
*-- can I lock this directly?
if rlock(tc_Alias)
    set REPROCESS to (ln_WasRepro)
    return .T.
endif

*-- Can't lock immediately 
*-- so try for a moment
clear typeahead
ln_Inkey = inkey(1)

*-- Schleife bis entweder ESC oder Sperrung
do while ln_Inkey <> 27 and not rlock(tc_Alias)
    ln_Inkey = inkey(1)
enddo

set REPROCESS to (ln_WasRepro)
return ln_Inkey <> 27        

*-- or like this
*--
*-- ll_ok = .F.
*-- for ln_i = 1 to 10
*-- if rlock(tc_Alias)
*--    ll_ok = .T.
*--    exit
*-- endif
*-- set REPROCESS to (ln_WasRepro)
*-- return ll_OK

You are moving the pointer and addressing the fields always
with the IN - clause but You do the REPLACE without selecting
the alias or using IN there. You should be on the right alias
as You are in the grid, but still I would make sure.

In this particular application users work with buffered table directly
where and when does the saving take place? - On the other hand, I don't think
that makes a difference here.


This is for the first impressions, I'll see if more rubbish comes to my mind