Opening a presentation file programatically throws an error. RSS

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  EJM

  Member

  190 Points

  415 Posts

  Opening a presentation file programatically throws an error.

  Nov 16, 2012 09:57 PM|LINK

  I have a method that uses Microsoft.Office.Interop.PowerPoint.Application interface to convert PowerPoint presentation slides into a jpeg files. In a serivce application that runs on Windows 2008 server it works without any issues.

  Now however, I'm writing a new web application that uses the same process and the degubber chokes on the Presentation.Open call wiht an error: "PowerPoint could not open file".

  My environment is Win 7, VS 2010. I'm using impersonation with a domain account that has admin privileges. The PowePoint file I'm trying to open is in the c:\temp folder which has NTFS rights of "everyone" set to full; file is NOT read-only, I can manually opent the file using a similar account as the domain account I'm using for impersonation. I don't know what the problem is. Can someone sugest what's going on? Thanks, EJM.

      using System;
      using System.Collections.Generic;
      using System.Linq;
      using System.IO;
      using System.Web;
      using System.Web.UI;
      using System.Web.UI.WebControls;

      using AjaxControlToolkit;
      using Microsoft.Office.Core;
      using Microsoft.Office.Interop.PowerPoint;
      using System.Threading;

  
      public partial class _Default : System.Web.UI.Page
      {
        private static int folderExtension;
        private static string tempSavePath,
                              fileName;

        protected void Page_Load(object sender, EventArgs e)
        {

        }

        private void Page_Error(object sender, EventArgs e)
        {
          Random r = new Random();
          int eventID = r.Next(1, 65535);
          Exception objErr = Server.GetLastError().GetBaseException();
          string err = "\nPage_Error Event" +
                  "\n\nError in: " + Request.Url.ToString() +
                  "\n\nError Message:" + objErr.Message.ToString() +
                  "\n\nStack Trace:" + objErr.StackTrace.ToString() +
                  "\n";
          uploadResult.Text = err.ToString();       
        }

        protected void AsyncFileUpload1_click(object sender, AsyncFileUploadEventArgs e)
        {
           // Temporary folder where the presentation file is uploaded.
           tempSavePath = @"c:\temp\";

           // Checks if there is a file present for uploading.
           if (AsyncFileUpload1.HasFile)
           {
              fileName = AsyncFileUpload1.FileName;

              try
              {
                  AsyncFileUpload1.SaveAs(tempSavePath + fileName);
              }
              catch (Exception ex)
              {
                  throw ex;
              }
              finally
              {
                  ConvertToJpegs();
              }
           }
           else
           {
              uploadResult.Text = "No file to upload.";
           }
       }

       // Converts the presentation slides into individual jpeg files.
       protected void ConvertToJpegs()
       {
          Microsoft.Office.Interop.PowerPoint.Application app = new Microsoft.Office.Interop.PowerPoint.Application();
          Microsoft.Office.Core.MsoTriState ofalse = Microsoft.Office.Core.MsoTriState.msoFalse;
          Microsoft.Office.Core.MsoTriState otrue = Microsoft.Office.Core.MsoTriState.msoTrue;

          Presentation pptPresentation = null;

          try
          {
           **>>> It break here with the ".Open" call <<<**  
              pptPresentation = app.Presentations.Open(tempSavePath + fileName, ofalse, ofalse, ofalse);
              pptPresentation.SaveAs(tempSavePath + ".", PpSaveAsFileType.ppSaveAsJPG, ofalse);
              Thread.Sleep(500);
          }
          catch (Exception ex1)
          {
              throw ex1;
          }
          finally
          {
              pptPresentation.Close();
          }
        }
      }

  Software engineering is a team sport.
• • Reply
  

  Prashant Kum...

  Star

  12346 Points

  1993 Posts

  Re: Opening a presentation file programatically throws an error.

  Nov 17, 2012 12:17 AM|LINK

  Opening office documents in a web application is not recommended and not supported by Microsoft.

  http://support.microsoft.com/kb/257757

  Although you can get your code to work by granting the user account under which your application is running the required permissions, you will always run into issues.

  Prashant
  • Edited by Frank Jiang - MSFT on Nov 26, 2012 12:46 AM
  • Edited by EJM on Nov 28, 2012 02:55 PM
  • Marked as answer by Frank Jiang - MSFT on Dec 12, 2012 06:18 AM
• • Reply
  

  EJM

  Member

  190 Points

  415 Posts

  Re: Opening a presentation file programatically throws an error.

  Nov 17, 2012 03:12 PM|LINK

  Hi, thanks for the post and the link to the article. I should share that I have this code running sucessfully in service application on the same server where it opens the PowerPoint in a non-interactive fashion and convert the slides into individual jpeg files.

   

  Software engineering is a team sport.