[CDO] MAPI.Session Logoff takes too long




I am using CDO 1.21 from C# in order to iterate through the entries in a users outlook address book (as OOM was too slow). Basically I take the Name field from each "message" and insert it into a ListBox. I shall paste my code at the end, and describe my problem first

If I call my MAPI.Sessions Logoff method when I have finished using it, then this method takes between 1 and 5 minutes to execute, but after that everything is fine

If I DONT call the MAPI.Sessions Logoff method, then I get my ListBox practically instantly filled and on the screen, but if I move the window or use the scroll bars, the program (and any running instances of Outlook) lock up, and only the task manager can kill them

I have seen this problem mentioned in the newsgroup but without a solution. Here is my code: (please note I use OOM and its PickFolder at the start to get my folders Entry and Store IDs

Object oResult;
MAPI.Message oMsg
MAPI.Messages oMsgs
MAPI.Folder oFolder
MAPI.Session oSession
// OOM Section to get Folder I
Microsoft.Office.Interop.Outlook.Application oa = new Microsoft.Office.Interop.Outlook.ApplicationClass()
Microsoft.Office.Interop.Outlook.NameSpace ns = oa.GetNamespace("mapi")
ns.Logon(Environment.UserName, Missing.Value, true, true)
Microsoft.Office.Interop.Outlook.MAPIFolder contacts = ns.PickFolder()

Object [] argsLogon = new Object[7];
Object[] argsGetFolder = new Object[2] {contacts.EntryID, contacts.StoreID}
contacts = null
ns = null
oa = null

oSession = new MAPI.Session()
argsLogon[0] = Missing.Value; // ProfileNam
argsLogon[1] = Missing.Value; // ProfilePasswor
argsLogon[2] = Missing.Value; // ShowDialo
argsLogon[3] = Missing.Value; // NewSessio
argsLogon[4] = Missing.Value; // ParentWindo
argsLogon[5] = Missing.Value; // NoMai
argsLogon[6] = Missing.Value; // ProfileInf
oSession.GetType().InvokeMember("Logon", BindingFlags.InvokeMethod, null, oSession, argsLogon)
// Get folder chosen above in PickFolder
oFolder =
(MAPI.Folder)oSession.GetType().InvokeMember("GetFolder", BindingFlags.Default |BindingFlags.GetProperty, null, oSession, argsGetFolder)

// Get folder name
oResult =
oFolder.GetType().InvokeMember("Name", BindingFlags.Default |BindingFlags.GetProperty, null, oFolder, null)
Console.WriteLine("Folder Name : {0}", oResult)

// Get AddressLis
oMsgs =
(MAPI.Messages)oFolder.GetType().InvokeMember("Messages", BindingFlags.Default |BindingFlags.GetProperty, null, oFolder, null)

// Get messages count
int totalMessages =
(int)oMsgs.GetType().InvokeMember("Count", BindingFlags.Default |BindingFlags.GetProperty, null, oMsgs, null);
Console.WriteLine("Count: {0}", totalMessages)
// Get the first message
oMsg =
(MAPI.Message)oMsgs.GetType().InvokeMember("GetFirst", BindingFlags.InvokeMethod, null, oMsgs, null)

for(int counter = 1; counter <= totalMessages; counter++

// Get Subject
ListViewItem i = new ListViewItem((string) oMsg.GetType().InvokeMember("Subject", BindingFlags.Default |BindingFlags.GetProperty, null, oMsg, null))
// Get each message
oMsg =
(MAPI.Message)oMsgs.GetType().InvokeMember("GetNext", BindingFlags.InvokeMethod, null, oMsgs, null)

oSession.Logoff(); // This bit causes problem

// The rest omitted.

Russell Mangel

Your code seemed to work okay, on my system.
Please try the following code, and see if things are better:

Russell Mangel
Las Vegas, NV

// Begin Code
MAPI.SessionClass oSession = new MAPI.SessionClass();
oSession.Logon(System.Environment.UserName, System.Reflection.Missing.Value,
true, true, System.Reflection.Missing.Value, false,

// Notice we are not logging into Outlook
Microsoft.Office.Interop.Outlook.Application oApplication = new
Microsoft.Office.Interop.Outlook.NameSpace oNameSpace =
Microsoft.Office.Interop.Outlook.MAPIFolder oMAPIFolder =

MAPI.Folder oFolder = (MAPI.Folder)oSession.GetFolder(oMAPIFolder.EntryID,

MAPI.Messages oMessages = (MAPI.Messages)oFolder.Messages;
MAPI.Message oMessage =

while(oMessage != null)
Console.WriteLine(" Subject: " + oMessage.Subject);

// Top of Loop
oMessage = null;
oMessage = (MAPI.Message)oMessages.GetNext();

// Let's time the Logoff() method
int begin = System.Environment.TickCount;


int end = System.Environment.TickCount;

Console.WriteLine("{0} milliseconds", (end - begin));

// End Code

Integer Software

Hi Russell,

Repeated runs of this example result the logoff function taking exactly
120 seconds each time. In other examples I have tried it always takes
exactly 60 seconds.

There must be some MS specified timeout value affecting things here.

I have XP Professional with latest updates
Office 2003 with latest updates
Visual Studio 2003 .net
Outlook runs in exchange mode and exchange server is exchange 2000
running on windows server 2000.

I shall continue to experiment.



Russell Mangel

This makes no sense, if you are connected to Exchange Server, you should
have a Global Address List.
If you send a Message from this Client using Outlook 2003, is the Global
address List available?
If so, then all of the code I sent should run okay.

One, question? How are you handling, the Outlook Security Dialogs?
As you probably know, the Security Dialogs, can be disabled by implementing
a special form in a public folder.

You seem to have a basic configuration problem here.

1. Make certain your client is in the Windows 2000 domain.
2. Login to the client with Administrator priveledges, and create a new
3. If this fails, you need to try another client Computer, in the domain.

Russell Mangel
Las Vegas, NV

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