I'd do it this way
I think some code was not in the right events and I had some screen ghosts when I was testing (could be my video driver though)
I don't like to put a simple one cell test in _SelectionChange since that event fires everytime. I prefer just _Change
Option Explicit
Private Sub ComboBox1_Change()
Range("G6").Value = Me.ComboBox1.Value
End Sub
Private Sub Worksheet_Activate()
ComboBox1.ListFillRange = "Dropdownlist"
Call pvtShowCombobox(Range("N6").Value = 1)
End Sub
Private Sub Worksheet_Change(ByVal Target As Range)
If Intersect(Target, Range("N6")) Is Nothing Then Exit Sub
Call pvtShowCombobox(Range("N6").Value = 1)
End Sub
Private Sub pvtShowCombobox(b As Boolean)
Application.ScreenUpdating = False
Application.EnableEvents = False
ComboBox1.Visible = b
Application.ScreenUpdating = True
Application.EnableEvents = True
DoEvents
End Sub