Formula to Delete Both Duplicates.

Sub Test()
    Dim Rng As Range
    Columns("A:A").Insert Shift:=xlToRight
    Set Rng = Range("A1:A" & Range("B65536").End(xlUp).Row)
    With Rng
        .FormulaR1C1 = "=COUNTIF(R1C2:R5C2,RC[1])"
        .Resize(, 2).AutoFilter Field:=1, Criteria1:=">1", Operator:=xlAnd
        .SpecialCells(xlCellTypeVisible).EntireRow.Delete
    End With
    Columns("A:A").Delete Shift:=xlToLeft
End Sub

Sub Delete_Duplicates()
Dim r As Long
Dim r2 As Long
Dim CurrentVal As String
Dim Unique As Boolean
    For r = 1 To Range("A65536").End(xlUp).Row
        CurrentVal = Range("A" & r).Value
        Unique = True
        For r2 = r + 1 To Range("A65536").End(xlUp).Row
            If Range("A" & r2).Value = CurrentVal Then
                Unique = False
                Range("A" & r2).EntireRow.Delete
                r2 = r2 - 1
            End If
        Next r2
        If Unique = False Then
            Range("A" & r).EntireRow.Delete
            r = r - 1
        End If
    Next r
End Sub