Crystal Reports :: Can't Convert To Pdf

In my project i need to convert crystal report to pdf. i am using below code. but throws the time out error. it didn't convert. my code is given below

Dim oStream As MemoryStream
oStream = DirectCast(report.ExportToStream(CrystalDecisions.[Shared].ExportFormatType.PortableDocFormat), MemoryStream)
Response.Clear()
Response.ClearContent()
Response.ClearHeaders()
Response.ContentType = "application/pdf"
Response.BinaryWrite(oStream.ToArray())
Response.Flush()
Response.Close()
'Response.End()
HttpContext.Current.ApplicationInstance.CompleteRequest()
Response.End i got Thread abort exception. so i used HttpContext.Current.ApplicationInstance.CompleteRequest().

now i didn't get any error. but it page doesn't open. How to me convert crystal report to pdf.