Hi,
Am getting this error "Object reference not set to an instance of an object". while trying to export crystal report in asp.net 2003 .. Below is my code.

Private Sub ExportClick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn_Go.Click        
Try                       
    Dim oStream As New MemoryStream 
    Me.Crystalreportviewer1.ParameterFieldInfo.Clear()  
    If Me.txtSTdate.Text.Trim.Length > 0 Then   
    Me.Crystalreportviewer1.ReportSource = Server.MapPath("pex_Summary.rpt")
    Dim ParamFields As ParameterFields = Me.Crystalreportviewer1.ParameterFieldInfo 
    Dim Per As New ParameterField  
    Per.ParameterFieldName = "Date"     
    Dim Period_Value As New ParameterRangeValue  
    Period_Value.StartValue = Me.txtSTdate.Text  
    Period_Value.EndValue = Me.txtCLdate.Text    
    Per.CurrentValues.Add(Period_Value)  
    ParamFields.Add(Per)              
   'Set Division Paramter            
    Dim GetDivisionValues As String   
    GetDivisionValues = Trim(Request.Form(ddl_division.UniqueID))   
    Per = New ParameterField        
    Per.ParameterFieldName = "Division"  
    Dim Division_Value As New ParameterDiscreteValue  
    If GetDivisionValues = "Select All" Then         
       Division_Value.Value = "*"                
    Else        
       Division_Value.Value = GetDivisionValues
    End If                
    Per.CurrentValues.Add(Division_Value)        
    ParamFields.Add(Per)                
    Select Case DropDownList1.SelectedItem.Text 

            Case "Rich Text (RTF)"
                '-----------------------------------------------------------
                oStream = crReportDocument.ExportToStream(_
                    CrystalDecisions.Shared.ExportFormatType.WordForWindows) ---> Error at this line.
                Response.Clear()
                Response.Buffer = True
                Response.ContentType = "application/rtf"
                '------------------------------------------------------------
                '------------------------------------------------------------
            Case "Portable Document (PDF)"
                oStream = crReportDocument.ExportToStream(_
                    CrystalDecisions.Shared.ExportFormatType.PortableDocFormat)
                Response.Clear()
                Response.Buffer = True
                Response.ContentType = "application/pdf"
    End Select 'export format
    Response.BinaryWrite(oStream.ToArray())
    Response.End()
    crReportDocument.SetDatabaseLogon("xx", "xx", "xx", "xx")                                Me.Crystalreportviewer1.RefreshReport()           
    Crystalreportviewer1.Visible = True      
Catch ex As Exception            
lblError.Text = ex.Message.ToString       
End Try    
End Sub

Am getting error at this below line :

oStream = crReportDocument.ExportToStream(_
                    CrystalDecisions.Shared.ExportFormatType.WordForWindows)

Can anyone pls help me.
Thanks.