Add members to Outlook GAL Distribution List using C# in a Console app

Question

I'm trying to write a C# console app that can programmatically update an Outlook distribution list (DL) in the Global Address List (GAL). I have permission to update this DL. I can do it interactively on my PC using Outlook, and I can do it in Perl code using Win32::NetAdmin::GroupAddUsers.

After adding a reference to COM library "Microsoft Outlook 14.0 Object Library", and then accessed via:

using Outlook = Microsoft.Office.Interop.Outlook;

I can successfully read from a DL, even recursing through DL's inside the "main" DL being searched. Here's that working code (critiques not needed for this piece):

private static List<Outlook.AddressEntry> GetMembers(string dl, bool recursive)
{
    try
    {
        List<Outlook.AddressEntry> memberList = new List<Outlook.AddressEntry>();

        Outlook.Application oApp = new Outlook.Application();
        Outlook.AddressEntry dlEntry = oApp.GetNamespace("MAPI").AddressLists["Global Address List"].AddressEntries[dl];
        if (dlEntry.Name == dl)
        {
            Outlook.AddressEntries members = dlEntry.Members;
            foreach (Outlook.AddressEntry member in members)
            {
                if (recursive && (member.AddressEntryUserType == Outlook.OlAddressEntryUserType.olExchangeDistributionListAddressEntry))
                {
                    List<Outlook.AddressEntry> sublist = GetMembers(member.Name, true);
                    foreach (Outlook.AddressEntry submember in sublist)
                    {
                        memberList.Add(submember);
                    }
                }
                else {
                    memberList.Add(member);
                }
            }
        }
        else
        {
            Console.WriteLine("Could not find an exact match for '" + dl + "'.");
            Console.WriteLine("Closest match was '" + dlEntry.Name +"'.");
        }

        return memberList;
    }
    catch
    {
        // This mostly fails if running on a PC without Outlook.
        // Return a null, and require the calling code to handle it properl
        // (or that code will get a null-reference excception).
        return null;
    }
}

I can use the output of that to examine the members closely, so I think I understand the DL/member objects a bit.

But, the following code will NOT add a member to a DL:

private static void AddMembers(string dl)
{
    Outlook.Application oApp = new Outlook.Application();
    Outlook.AddressEntry ae = oApp.GetNamespace("MAPI").AddressLists["Global Address List"].AddressEntries[dl];
    try {
        ae.Members.Add("EX", "Tuttle, James", "/o=EMC/ou=North America/cn=Recipients/cn=tuttlj");
    }
    catch (Exception ex)
    {
        Console.WriteLine(ex.Message);
    }
    ae.Update();
}

The arguments to Members.Add() are defined here, and the values shown in my code come exactly from examining my own Member object from another DL.

The exception displayed is simply "The bookmark is not valid." A similar question was asked before, but the solution was to use P/Invoke or LDAP. I really have no idea how to use P/Invoke (strictly a C# and Perl programmer, not a Windows/C/C++ programmer), and I don't have access to the LDAP server, so I really want to get this working through the Microsoft.Office.Interop.Outlook objects.

Any help is GREATLY appreciated!

Answer 1

After experimenting with several different .NET objects, using System.DirectorServices.AccountManagement as posted in Adding and removing users from Active Directory groups in .NET is what finally code this working for me. Closing out my own question.