ddressOf DialogHookFunction)
        '.flags = .flags Or OFN_ENABLEHOOK Or OFN_EXPLORER
        ''Set m_oEventSink = EventSink
    End If
    
    ' Make new filter with bars (|) replacing nulls and double null at end
    Dim ch As String, i As Integer
    For i = 1 To Len(Filter)
        ch = Mid$(Filter, i, 1)
        If ch = "|" Or ch = ":" Then
            s = s &amp; vbNullChar
        Else
            s = s &amp; ch
        End If
    Next
    ' Put double null at end
    s = s &amp; vbNullChar &amp; 