I know how to call a Macro when one cell is selected as below. But this only
works when cell B1 is selected.

But anybody knows how to trigger the macro when any cell in one column is
selected (E.g when cell from B1 to B1000 is selected...) Thanks a lot!

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Private Sub Worksheet_Selectionchange(ByVal Target As Range)

If Target.Address = "$B$1" Then
Call OpenCalendar
End If
End Sub
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