Can I read an Outlook (2003/2007) PST file in C#?

Question

Is it possible to read a .PST file using C#? I would like to do this as a standalone application, not as an Outlook addin (if that is possible).

If have seen other SO questions similar to this mention MailNavigator but I am looking to do this programmatically in C#.

I have looked at the Microsoft.Office.Interop.Outlook namespace but that appears to be just for Outlook addins. LibPST appears to be able to read PST files, but this is in C (sorry Joel, I didn't learn C before graduating).

Any help would be greatly appreciated, thanks!

EDIT:

Thank you all for the responses! I accepted Matthew Ruston's response as the answer because it ultimately led me to the code I was looking for. Here is a simple example of what I got to work (You will need to add a reference to Microsoft.Office.Interop.Outlook):

using System;
using System.Collections.Generic;
using Microsoft.Office.Interop.Outlook;

namespace PSTReader {
    class Program {
        static void Main () {
            try {
                IEnumerable<MailItem> mailItems = readPst(@"C:\temp\PST\Test.pst", "Test PST");
                foreach (MailItem mailItem in mailItems) {
                    Console.WriteLine(mailItem.SenderName + " - " + mailItem.Subject);
                }
            } catch (System.Exception ex) {
                Console.WriteLine(ex.Message);
            }
            Console.ReadLine();
        }

        private static IEnumerable<MailItem> readPst(string pstFilePath, string pstName) {
            List<MailItem> mailItems = new List<MailItem>();
            Application app = new Application();
            NameSpace outlookNs = app.GetNamespace("MAPI");
            // Add PST file (Outlook Data File) to Default Profile
            outlookNs.AddStore(pstFilePath);
            MAPIFolder rootFolder = outlookNs.Stores[pstName].GetRootFolder();
            // Traverse through all folders in the PST file
            // TODO: This is not recursive, refactor
            Folders subFolders = rootFolder.Folders;
            foreach (Folder folder in subFolders) {
                Items items = folder.Items;
                foreach (object item in items) {
                    if (item is MailItem) {
                        MailItem mailItem = item as MailItem;
                        mailItems.Add(mailItem);
                    }
                }
            }
            // Remove PST file from Default Profile
            outlookNs.RemoveStore(rootFolder);
            return mailItems;
        }
    }
}

Note: This code assumes that Outlook is installed and already configured for the current user. It uses the Default Profile (you can edit the default profile by going to Mail in the Control Panel). One major improvement on this code would be to create a temporary profile to use instead of the Default, then destroy it once completed.

Answer 1

The Outlook Interop library is not just for addins. For example it could be used to write a console app that just reads all your Outlook Contacts. I am pretty sure that the standard Microsoft Outlook Interop library will let you read the mail - albeit it will probably throw a security prompt in Outlook that the user will have to click through.

EDITS: Actually implementing mail reading using Outlook Interop depends on what your definition of 'standalone' means. The Outlook Interop lib requires Outlook to be installed on the client machine in order to function.

// Dumps all email in Outlook to console window.
// Prompts user with warning that an application is attempting to read Outlook data.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Outlook = Microsoft.Office.Interop.Outlook;

namespace OutlookEmail
{
class Program
{
    static void Main(string[] args)
    {
        Outlook.Application app = new Outlook.Application();
        Outlook.NameSpace outlookNs = app.GetNamespace("MAPI");
        Outlook.MAPIFolder emailFolder = outlookNs.GetDefaultFolder(Microsoft.Office.Interop.Outlook.OlDefaultFolders.olFolderInbox);

        foreach (Outlook.MailItem item in emailFolder.Items)
        {
            Console.WriteLine(item.SenderEmailAddress + " " + item.Subject + "\n" + item.Body);
        }
        Console.ReadKey();
    }
}
}

Answer 2

I went through and did the refactoring for subfolders

    private static IEnumerable<MailItem> readPst(string pstFilePath, string pstName)
    {
        List<MailItem> mailItems = new List<MailItem>();
        Microsoft.Office.Interop.Outlook.Application app = new Microsoft.Office.Interop.Outlook.Application();
        NameSpace outlookNs = app.GetNamespace("MAPI");

        // Add PST file (Outlook Data File) to Default Profile
        outlookNs.AddStore(pstFilePath);

        string storeInfo = null;

        foreach (Store store in outlookNs.Stores)
        {
            storeInfo = store.DisplayName;
            storeInfo = store.FilePath;
            storeInfo = store.StoreID;
        }

        MAPIFolder rootFolder = outlookNs.Stores[pstName].GetRootFolder();

        // Traverse through all folders in the PST file
        Folders subFolders = rootFolder.Folders;

        foreach (Folder folder in subFolders)
        {
            ExtractItems(mailItems, folder);
        }
        // Remove PST file from Default Profile
        outlookNs.RemoveStore(rootFolder);
        return mailItems;
    }

    private static void ExtractItems(List<MailItem> mailItems, Folder folder)
    {
        Items items = folder.Items;

        int itemcount = items.Count;

        foreach (object item in items)
        {
            if (item is MailItem)
            {
                MailItem mailItem = item as MailItem;
                mailItems.Add(mailItem);
            }
        }

        foreach (Folder subfolder in folder.Folders)
        {
            ExtractItems(mailItems, subfolder);
        }
    }

Answer 3

As already mentioned in one of your linked SO questions, I'd also recommend using the Redemption library. I'm using it in a commercial application for processing Outlook mails and performing various tasks with them. It's working flawlessly and prevents showing up the annoying security alerts. It would mean using COM Interop, but that shouldn't be a problem.

There's a library in that package called RDO which is replacing the CDO 1.21, which lets you access PST files directly. Then it's as easy as writing (VB6 code):

set Session = CreateObject("Redemption.RDOSession")
'open or create a PST store
set Store = Session.LogonPstStore("c:\temp\test.pst")
set Inbox = Store.GetDefaultFolder(6) 'olFolderInbox
MsgBox Inbox.Items.Count

Answer 4

You can use pstsdk.net: .NET port of PST File Format SDK library which is open source to read pst file without Outlook installed.

Answer 5

Try Pstxy.

It provide .Net API to read Outlook PST & OST file without need for Outlook installed.

It has a free version to extract mail content (text, html & rtf). The plus version support attachments, too.

Answer 6

For those mentioning that they don't see the Stores collection:

The Stores collection was added in Outlook 2007. So, if you're using an interop library created from an earlier version (in an attempt to be version independent - this is ver common) then this would be why you won't see the Stores collection.

Your only options to get the Stores are to do one of the following:

• Use an interop library for Outlook 2007 (this means your code won't work for earlier versions of Outlook).
• Enumerate all top level folders with Outlook object model, extract the StoreID of each folder, and then use CDO or MAPI interfaces to get more information about each store.
• Enumerate the InfoStores collection of CDO session object, and then use the fields collection of InfoStore object in order to get more information about each store.
• Or (the hardest way) use extended MAPI call (In C++): IMAPISession::GetMsgStoresTable.

Answer 7

We are going to use this, to provide a solution that doesn't rely on outlook.

http://www.independentsoft.de/pst/index.html

It is very expensive, but we hope that will lower development time and increase quality.

Answer 8

I found some resources directly from Microsoft which may be helpful for completing this task. A search on MSDN reveals the following.

• How to use the Microsoft Outlook Object Library to retrieve a message from the Inbox by using Visual C#
• How to use the Microsoft Outlook Object Library to retrieve an appointment by using Visual C#

Note that when you're adding a reference to Microsoft.Office.Interop.Outlook, the documentation insists that you do so via the .NET tab instead of the COM tab.

Answer 9

The MAPI API is what you are looking for. Unfortunately it is not available in .Net so I'm afraid you will have to resort to calling unmanaged code.

A quick Google reveals several wrappers available, maybe they work for you?

This might also be helpful: http://www.wischik.com/lu/programmer/mapi_utils.html

Answer 10

This .NET connector for Outlook might get you started.

Answer 11

Yes, with Independentsoft PST .NET is possible to read/export password protected and encrypted .pst file.

Answer 12

Really usefull code. If you have pst and store your messages in its root (without any directory), then you can use the following in method readPst:

 MAPIFolder rootFolder = outlookNs.Stores[pstName].GetRootFolder();
 Items items = rootFolder.Items;
 foreach (object item in items)
 {
      if (item is MailItem)
      {
           MailItem mailItem = item as MailItem;
           mailItems.Add(mailItem);
      }
 }

Answer 13

Yes you can use MS Access and then you either import your pst content or just link it (slow!).