>i what to know who to do a Automatic sumary item of grid´s column

Marvin,
Do you want to add a column to the grid with a sum of items in a specific row? Or do you want to see the total of all the items on the grid (for example the total cost on a grid of invoice items?

If the first, then in the control source of the column you put the calculation, with an = sign in front of it: =Itemcost * ItemCount

If the second, then you'll need to have a form method that SUM()s the values in the grid and stores it to a form property. Add a label or a textbox to your form to show this information.

You'll need to call the form whenever you open the form, whenever you refresh the grid and whenever you change an item on the grid that is part of the SUM.

HTH
Barbara