Nicola,
I have seen the same thing happen, and usually use a view instead of a relation to show data from multiple tables in a grid.

Are both forms using private datasessions? If not, the your data may be changed in the second form and your relation disrupted.

Is there code in the "Activate" method of the form and (if you have a pageframe) the pageframe page? The Activate code is run when you return to a form from another form and this may be disrupting the relationship somehow.

What happens if you refresh the grid in the Activate code so it is always updated when you return from the second form?

HTH
Barbara


>I have a grid on a form with "table1" as RecordSource .
>I set a column with a ControlSource like this:
>
>IIF(EMPTY(table2.item_code), ' ', '#')
>
>table2 is related with table1 based on item_code.
>When I activate another form (the form with the grid looses focus)
>I have a "total" refresh of the column grid with the same value
>(' ' or '#' depending on the value of the current grid row)
>
>Any suggestion ?