Can't print correctly by using Adobe Reader 9.1.2

Question

The following code in OCX is being used in my web application to print PDF directly with Adobe Reader 5.1, and it works fine!
When Adobe Reader is upgraded to 9.1.2, it no longer works. Printouts often cannot be printed correctly. However, when I add the code in red, the printouts can be printed correctly again.
Anyway, I don't want Open and Close Adobe Reader during direct printing.
Anyone knows why FilePrintSilent doesn't work? and how to solve it?
Thanks in advance!
William
    ''''''''''' Use ddeml to communicate with acrobat reader '''''''''''
    On Error GoTo ErrPrinting1
    Dim a
    Set a = CreateObject("AcroExch.Document")
    Dim lRet As Boolean
    Dim sValue As String
    sValueOpen = "[DocOpen(" & localFileName & ")]"
    sValuePrint = "[FilePrintSilent(" & localFileName & ")]"
    sValueClose = "[DocClose(" & localFileName & ")]"
    DDE_Initialize
    DDE_CreateStringHandles "acroview", "control", ""
    ' Open the conversation.
    If (g_hDDEConv = 0) Then
        g_hDDEConv = DDE_Connect
    End If
    If g_hDDEConv Then
        ' Perform the transaction.
        lRet = DdeClientTransaction(sValueOpen, Len(sValueOpen), g_hDDEConv, 0, 0, XTYP_EXECUTE, 5000, 0)
        lRet = DdeClientTransaction(sValuePrint, Len(sValuePrint), g_hDDEConv, 0, 0, XTYP_EXECUTE, 5000, 0)
        Sleep 800
        lRet = DdeClientTransaction(sValueClose, Len(sValueClose), g_hDDEConv, 0, 0, XTYP_EXECUTE, 5000, 0)
        If (lRet) Then
            Debug.Print "DDE Execute Success."
        Else
            Debug.Print "DDE Execute Failure."
        End If
    Else
        Debug.Print "DDE Connect Failure"
        printToPrinter = "DDE Connect Failure"
        Exit Function
    End If
    ' Release the memory.
    DDE_FreeStringHandles
    DDE_Uninitialize
    Set a = Nothing
    ''''''''''' end '''''''''''

Answer 1

We have PDF documents stored on server-side, the ActiveX control and Adobe Reader are installed on client-side.
When users open our web page, click our "Print weekly report directly" button, the ActiveX control on client will be called, and perform the above coding. It tries to download the PDF document from server to client, and pass it to the printer on client silently by using FilePrintSilent function.
The report can be printed, but not correct. It involves some unexpected characters which should be English or Traditional Chinese originally, as shown in the attached picture.
Thanks in advance!
William