Trigger macro on click

One way:

Option Explicit

Private Sub Worksheet_SelectionChange(ByVal Target As Range)

    If Target.Cells.Count > 1 Then Exit Sub
    
    If Target.Row > 1 Then 'exclude header row
        If Target.Column = 2 Or Target.Column = 8 Then
            OpenCalendar
        End If
    End If

End Sub

Originally Posted by Palmetto

One way:

Option Explicit

Private Sub Worksheet_SelectionChange(ByVal Target As Range)

    If Target.Cells.Count > 1 Then Exit Sub
    
    If Target.Row > 1 Then 'exclude header row
        If Target.Column = 2 Or Target.Column = 8 Then
            OpenCalendar
        End If
    End If

End Sub

Yes that line would be good housekeeping