This requires a multi-part answer, but it is fairly
simple.
First, set up your option group On_Click so that
If Me.NotaryYN = yes Then
Me.NotaryExp.SetFocus
End If
Next for your text box you need to set up another piece
for its On_Exit Event so that
If IsNull(Me.NotaryExp) Then
--it is nice to include a Message Box at this point--
MsgBox "This field must contain data to continue!",
vbOKOnly
Me.Field.SetFocus - this can be any field other than
NotaryExp
Me.NotaryExp.SetFocus
End If
This will prevent the end user from leaving the field
NotaryExp without data. However, from personal
experience, nothing stops them from typing in garbage
data. I've set this up on several databases, and find
the field sometimes contains "N/A" or just some random
letter or number...whatever is required to get them past
that box. And you can try applying If Then Statements to
deny them that option, but they still find a combination
of junk to throw in their. Just look at it as job
security for a database administrator!