One quick thing to try is to capitalize the "t" in "text" like below:

Dim SocSecNum As New Binding("Text", ObjDatos_personales_sol1, "Datos_personales_sol.num_control")

>Cathi:
>
>I try your example of regex.replace but when I try to add the biding to the textbox control it said did not accept null values. Before I try to add the databidings to the control I create the row and add the row to the dataset and also add some values to the field that was defined as no nulls.
>
>The following line is where I get the problem.
>
> Me.TextBox2.DataBindings.Add(SocSecNum)
>
>socsecnum was declared in the following line.
>
>Dim SocSecNum As New Binding("text", ObjDatos_personales_sol1, "Datos_personales_sol.num_control")
>
>and the code that initialize the row for the dataset is the following
>
>Me.BindingContext(ObjDatos_personales_sol1, "Datos_personales_sol").EndCurrentEdit()
> dr = ObjDatos_personales_sol1.Tables(0).NewRow()
> dr(0) = Space(1)
> dr(3) = Space(1)
> dr(4) = Space(1)
>
> ObjDatos_personales_sol1.Tables(0).Rows.Add(dr)
>
> Me.BindingContext(ObjDatos_personales_sol1, "Datos_personales_sol").Position = ObjDatos_personales_sol1.Tables(0).Rows.Count - 1
>
>All that ocurred before adding the socsecnum object to the text box.
>
>what I am doing wrong?