Forms :: Multirecord Continuous Form - Combobox Beforeupdate Does Not Work

I have a multirecord continuous form that displays the results of a query. At the end of each row there is a combobox displaying a list of form names. The user selects one of these forms from the list and program fetches the detail data in that selected form corresponding to the row where the cursor is. Now the beforeupdate or aferupdate or onclick functions do not work. Her are the properties of the combobox as JPG files and the code of the not working function.

Code:
Private Sub Sbox_AfterUpdate()
Dim ForName As String
Dim ParName As String
Dim QryName As String
MsgBox "after update combo"
ParName = Me.Form.Name
Select Case Me.Sbox.Value

[Code] .....