I have an access table that holds customer information and another table that holds orders associated with those customers. I want to place a textbox on the form that is used to enter customer information that alerts the salesperson if there is an order associated with that customer based on matching a customer number between those two tables. So, if there are no orders the textbox is blank, but if there are turn it red and display some text. If there are orders I want to show a button that I will use to open a form to show those orders.
I know enough about access to create the queries and forms and such, but I don't know how to change the behaviour of a textbox based on the results of a query.