using (Aspose.Slides.Presentation pres = new Aspose.Slides.Presentation(Server.MapPath("~/demo.pptx")))
{
pres.Save(Server.MapPath("~/demoDefault.pdf"), Aspose.Slides.Export.SaveFormat.Pdf);
}
System.NullReferenceException
TargetSite : Aspose.Slides.Animation.FilterEffectType (System.String)