I have two forms (MS Access 2010). The main form allows an end user to select certain materials. Once they select an item and then press 'Process', it the material has serial numbers, it displays the second form (acDialog), so the end user can select the serial numbers they're processing. What I would like to happen is if an end user clicks the x at the top of the second form (the serial number selector), I want all execution to stop. I thought if I create an Err object it would do that, but it throws the error and then continues execution on the main form. Is there a way to completely stop execution of the code?