Thanks, Chris. I'm using VFP6.0 SP4. Nobody confirmed, if this problem still exists in VFP7 or not. Anyway, once I set buffering mode to 5 on read-only table, the problem went away. At least, I could not reproduce it anymore. We'll see in a couple of days, if this was a fix indeed...

Thanks a lot.

>Hi Nadia
>
>I used to find this problem with VFP3, with an order processing form displaying order items in a grid. There were several relations set to readonly and read-write tables from the order headers table. The read-write tables were all table-buffered optimistically. This is the fix I used:
> =RLOCK("orders") && Header, displayed on form
> =RLOCK("odlines") && Items, displayed in grid
> =RLOCK("stylcols") && stock table, not displayed but updated
> =RLOCK("styles") && read-only, displayed in grid
> =RLOCK("colours") && read-only, displayed in grid
> UNLOCK ALL
>
>Note that checking the lock status on any of the tables gives a negative result. And of course with optimistic locking, nothing should have been locked anyway. The RLOCK() is essential - just issuing UNLOCK doesn't work.
>I usually place this code in a method on the grid called .bugfix() <s>, and call it after any child tables ("odlines" and "stylcols") are written to.
>
>HTH
>
>ChrisM, London, still winter.