Error Checking and SetFocus

When a user makes a choice from ListBox1, I populate ListBox2 (unbounded) based on the value of ListBox1, and set the focus to the first line "-----", forcing the User to make a choice.

On ListBox2 I use the LostFocus() event to check whether the user made a choice other than "-----". If the value is still "-----" I display a message and set the focus back to ListBox2.

Problem - the focus doesn't go to ListBox2 the second time, but moves to the next control.

I tried moving the Error Checking to the Form_BeforeUpdate event, and it works on the first pass, but if the User attempts to Save the record a second time without making a choice, Access goes ahead and moves to the next record.

Suggestions?

Thanks,
Charlie

One option, disable the subsequent fields by default and enable only after a valid selection has been made.