From: rumkus on
Rigt click on the sheet tab and click "view code".
Copy below code and paste it on the code window.
A6 as the cell with validation. Change it to your cell address.
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Private Sub Worksheet_Change(ByVal Target As Range)
If Not Intersect(Target, Me.Range("A6")) Is Nothing Then
Target.Offset(0, 1).Select
End If
End Sub