I have 6 option groups on my form and every time I try to update another control on my form I get the "2427 - You entered an expression that has no value" error. I tracked it down to the 6 option groups on my form. When I remove those from my form I no longer get the error. When I say I get this when I update another control on my form I mean after I update that control and recalc the form is when I get the error. Why would these cause that error message? I'm not sure I understand why this happens only with option groups.