I have a form which enters data into a table. Field total amount (FieldF) is an equation of ((FieldE*FieldD) * (FieldA+FieldB+FieldC)). When I enter the equation into the text box the correct amount is shown, but it is not linked to the field in the Table where FieldF, the control source has been replaced by the equation. I have tried to use a query using FieldF: ((FieldE*FieldD) * (FieldA+FieldB+FieldC)) selecting FieldA's Table in the table column. This didn't work either and returned a automation error? any suggestions.