Require that data be entered for a field

1. In table Design view, in the upper portion of the window, click the field that you want to require data entry for.
   
   
2. In the lower portion of the window on the General tab, click the Required property box, and then click Yes.

   When you save changes to your table, Microsoft Access gives you the option to check to see whether the field has a value in all existing records. However, you can require that a value be entered in this field in all new records even if there are existing records with Null (blank) values in the field that aren't going to be changed.

Note   The Required property is enforced at the table level, so if you set this property to Yes, the field must have a value in all instances in which data might be entered in the field — in the table, in forms and datasheets based on the table, when a macro or Visual Basic for Applications code sets the value of the field, or when data is imported into the table.