>The grid, the column are not readonly. The table is not opened with the noupdate option. I can change the values in the other columns.
>The result of my tests is, that every control I added dynamicly to a column of the grid is readonly. I can change the attribute to .f., but if I click into the grid, the readonly attribute is changed automatic to .t.. Any idea?
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Not unless you have some code in the column or control that changes this property to read-only. What about code in the checkbox class you are dropping on the column? How are you adding the checkbox to the column? Are you putting the grid in edit mode first them dropping the checkbox into the column? Or is the control added programmatically at runtime? At this point it looks like the problem is some code changing this property. Set a break point on when the ReadOnly property value changes for that control.