You're on the right track. First though, you have to make the event procedures in form1 accessible to Form2. Open Form1 in design view, and change the After_Update event procedures for the three combo boxes from Private Sub .... to Public Sub ... Save the changes.
'how do I run the after update event for cmbArea?
Use this: [Forms]![frm20MainStatus].cmbArea_AfterUpdate
So your code will look like this:
Code:
Private Sub btnStation_Click()
Dim AreaLookUp As String, SubLookup as String
AreaLookUp = DLookup("[Area]", "[Qryxreference]", "[Station]='" & [Forms]![frm30UserData]![lstStation] & "'")
[[Forms]![frm20MainStatus]![cmbArea] = AreaLookUp ' That is correct
[Forms]![frm20MainStatus].cmbArea_AfterUpdate
'
' Same concept for the second combo
'
SubLookUp = DLookup("[Subarea]", "[Qryxreference]", "[Station]='" & [Forms]![frm30UserData]![lstStation] & "'")
[Forms]![frm20MainStatus]![cmbSub] = SubLookUp
[Forms]![frm20MainStatus].cmbSub_AfterUpdate
'
' And the combo for Station
'
[Forms]![frm20MainStatus]![cmbStation] = '" & [Forms]![frm30UserData]![lstStation] & "'" ' This wasn't quite right - missing single quote
[Forms]![frm20MainStatus].cmbSub_AfterUpdate
end sub
That should be close. The trick is to make the After Update events of the combos in Form1 public, so they can be called from outside the form (as long as it is open).