1) System.Runtime.InteropServices.COMException (0x800401E3)...
2) 0x800401e3 "Operation unavailable"
3) Object reference not set to an instance of an object
4) System.Runtime.InteropServices.COMException (0x80080005): Retrieving the COM class factory for component with CLSID {0006F03A-0000-0000-C000-000000000046} failed due to the following error: 80080005.
5) Creating an instance of the COM component with CLSID {0006F03A-0000-0000-C000-000000000046} from the IClassFactory failed due to the following error: 80010001.
As GetActiveObject function just work on debug mode. This forum "Marshal.GetActiveObject(“Outlook.Application”) throws MK_E_UNAVAILABLE when debugging with elevated privileges" mentioned that the reason is different user level running which Visual Studio runs as Administrator and Outlook was opened as user. I tried to change Privilege Level of my program and Outlook as "Run this program as an administrator", but it will prompt a User Account Control message box in every start, although I can adjust notification level to lower, but I don't want to do that. Besides, my program file will automatically deleted and copied from server if there is any file changed, so it is not a good practice.
Basically, Outlook.NameSpace function works fine if you don't mind running Outlook in background. Because I have to monitor the status of Outlook whether already got and deleted emails, so the function is also not work for me.
The example code of Microsoft website above describes getting a current instance of Outlook which need use GetActiveObject function, but it is not totally correct. If Outlook application is installed and create an object (Obj = new Outlook.Application) in program, the program can automatically find and assign the current instance of Outlook to the object, therefore I use create an object instead of use GetActiveObject function.
Here's my example.
Minimum requirement for my example:
1) Microsoft Outlook application must be installed in the computer.
2) If the computer has multiple outlook's profiles installed, you should define one of outlook's profile as default in Mail setting otherwise Outlook will prompt a profile screen for selection when open in every time. How to set default: Control Panel->Mail->General->select "Always use this profile".
3) Enable Programmatic Access in Microsoft Outlook. How to: File->Outlook->Trust Center->Trust Center Settings->Programmatic Access->select "Never warn me about suspicious activity".
Pesudo-code
Start a program and call the below function (example code below).
1) Detect whether Outlook is opened.
1.1) If yes then close Outlook process with hidden and shown.
1.2) If no then Open Outlook.
1.3) Waiting up to 5 mins If cannot found any Outlook process then raise error and exit.
2) Create an new object. e.g. oOLApp = new Outlook.Application().
3) Double Check whether Outlook is opened with profile successfully otherwise raise error and exit.
4) Detect Outlook connection status whether already connected to Microsoft Exchange.
4.1) Waiting up to 5 mins if the status is not connected then raise error and exit.
5) Waiting Sync is completed.
Here's the code
using Outlook = Microsoft.Office.Interop.Outlook;
Outlook.Application oOLApp = null;
private void form1_Load(object sender, EventArgs e)
{
try
{
this.FindnOpenOutlook();
while (this.GetEmail.Count >0)
{
// ......
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
private void FindnOpenOutlook()
{
// 1 & 1.1) Find and kill all outlook process.
foreach (Process p in Process.GetProcesses().Where(x => x.ProcessName.ToString().ToUpper() == "OUTLOOK"))
{
p.Kill();
p.WaitForExit();
}
// 1.2) Open Outlook application.
ProcessStartInfo sinfo = new ProcessStartInfo();
sinfo.UseShellExecute = true;
sinfo.WindowStyle = ProcessWindowStyle.Normal;
sinfo.FileName = "outlook.exe";
using (Process exeProcess = Process.Start(sinfo)) { exeProcess.WaitForInputIdle(); }
sinfo = null;
// 1.3) Waiting up to 5 mins if cannot found Outlook process then raise error.
dtLast = DateTime.Now;
while (Process.GetProcessesByName("OUTLOOK").Count() == 0)
{
Thread.Sleep(500);
if (DateTime.Now > dtLast.AddMinutes(5)) { throw new Exception("Cannot open Outlook application."); }
}
// 2) Create an new object
// If Outlook application found then oOLApp.Session.CurrentProfileName is not null otherwise oOLApp is null.
oOLApp = new Outlook.Application(); //instead of oOLApp = (Outlook.Application)Marshal.GetActiveObject("Outlook.Application");
// 3) Check whether Outlook application is opened with outlook profile successfully.
if ((oOLApp.Session.CurrentProfileName == null) || (oOLApp.Session.CurrentProfileName == "")) { throw new Exception("Cannot find Outlook application"); }
// 4 & 4.1) Detect Outlook connection status whether already connected to Microsoft Exchange.
// If not using Cached Exchange Mode, then check olOnline instead of olCachedConnectedFull.
dtLast = DateTime.Now;
while (oOLApp.Session.ExchangeConnectionMode != Outlook.OlExchangeConnectionMode.olCachedConnectedFull)
{
Thread.Sleep(500);
if (DateTime.Now > dtLast.AddMinutes(5)) { throw new Exception("Exchange Connection failed. "); }
}
// 5) Waiting Sync is completed.
syncObjs = oOLApp.Session.SyncObjects;
for (int i = 1; syncObjs.Count >= i; i++)
{
syncAObj = syncObjs[i];
syncAObj.SyncStart += syncObj_SyncStart;
syncAObj.SyncEnd += syncObj_SyncEnd;
if (syncAObj != null)
{
IsSyncFinished = false;
syncAObj.Start();
while (IsSyncFinished == false) { Thread.Sleep(500); } // waiting sync completed
}
System.Runtime.InteropServices.Marshal.ReleaseComObject(syncAObj);
}
}
Close Outlook function
public void CloseMSOutlook()
{
try
{
if (oOLApp != null)
{
oOLApp.Session.Logoff();
oOLApp.Quit();
}
}
catch (Exception ex)
{ throw ex; }
finally
{
if (oOLApp != null) { System.Runtime.InteropServices.Marshal.ReleaseComObject(oOLApp); }
GC.Collect();
GC.WaitForPendingFinalizers();
foreach (Process p in Process.GetProcesses().Where(x => x.ProcessName.ToString().ToUpper() == "OUTLOOK"))
{
p.Kill(); p.WaitForExit();
}
};
}
Coding in Program.cs
Adding below coding in a Program.cs of C#.net to check whether the application is running, if not found then run the application otherwise ignore.
{
static class Program
{
private static Mutex mutexOLEmail = null;
[STAThread]
static void Main()
{
string sAppExePath = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);
try
{
mutexOLEmail = new Mutex(true, "{myOLEmailPgm} " + sAppExePath.Replace("\\", ""));
if (mutexOLEmail.WaitOne(TimeSpan.Zero, false))
{
Application.Run(form1);
}
}
catch (Exception ex)
{ MessageBox.Show(ex.Message); }
finally
{
if (mutexOLEmail != null) { mutexOLEmail.Close(); }
mutexOLEmail = null;
}
}
}
}
The above coding will prevent to re-open the program, so now you can add a trigger, for example runs the program at 9am everyday or every 5 minutes, in Task Scheduler. 