Ошибка получения объекта com 2147221021 0x800401e3 операция недоступна

i am try to hook to outlook application from windows Service but getting an exception Operation unavailable (Exception from HRESULT: 0x800401E3 (MK_E_UNAVAILABLE)) here is my code.

   public void ItemSendEvent()
    {
        try
        {
           if (Process.GetProcessesByName(ApplicationConstants.OUTLOOK_PROCESS_NAME).Count() > 0)
                {
                    // If so, use the GetActiveObject method to obtain the process and cast it to an Application object.
                    outlookApplication = Marshal.GetActiveObject(ApplicationConstants.OUTLOOK_APPLICATION_NAME) as Microsoft.Office.Interop.Outlook.Application;
                    Microsoft.Office.Interop.Outlook.NameSpace nameSpace = outlookApplication.GetNamespace(ApplicationConstants.OUTLOOK_NAME_SPACE);
                    nameSpace.Logon("", "", Missing.Value, Missing.Value);
                    nameSpace = null;
                    outlookApplication.ItemSend += outlookApplication_ItemSend;
                }
                log.Info("Outlook Item Send event registered successfully.");
        }
        catch (System.Exception ex)
        {
            log.Error("Exception occurred while registering Outlook Item Send event. " + ex.Message);
        }
    }

but the same code when i launch it through Windows Form Application its working Fine. i gone through some site’s and they were saying that outlook object is not in ROT Table. what will be the solution.

asked Jun 2, 2016 at 10:58

Old, but still significant thread.

I collided with this error when tried to access Outlook data using the MS example.

Treating the error in a Try / Catch block and offering the option of newing Outlook solves the problem:

const int ERROR_HRESULT_0x800401E3_MK_E_UNAVAILABLE= -2147221021;
        Outlook.Application application = null;
        // Check whether there is an Outlook process running.
        if (Process.GetProcessesByName("OUTLOOK").Any())
        {
            try
            {
                // If so, use the GetActiveObject method to obtain the process and cast it to an Application object.
                application = Marshal.GetActiveObject("Outlook.Application") as Outlook.Application;
                }
            }
            catch (Exception ex)
            {
                //This is the branch where you can get correctly the current Outlook instance
                if (ex.HResult == ERROR_HRESULT_0x800401E3_MK_E_UNAVAILABLE)
                {
                    application = new Outlook.Application();
                }
            }
        }
        else
        {
            application = new Outlook.Application();
        }

Although the newing trick functions, no other Outlook instance is created, as Outlook behaves like a Singleton.

I only tested it with Office 365 64 bits installed.

answered Nov 15, 2020 at 15:44

you don’t need to have your application as a service to get it on the background …

if your winform work well, just put your winform in background running on the systray for instance

answered Nov 8, 2016 at 21:11

i am try to hook to outlook application from windows Service but getting an exception Operation unavailable (Exception from HRESULT: 0x800401E3 (MK_E_UNAVAILABLE)) here is my code.

   public void ItemSendEvent()
    {
        try
        {
           if (Process.GetProcessesByName(ApplicationConstants.OUTLOOK_PROCESS_NAME).Count() > 0)
                {
                    // If so, use the GetActiveObject method to obtain the process and cast it to an Application object.
                    outlookApplication = Marshal.GetActiveObject(ApplicationConstants.OUTLOOK_APPLICATION_NAME) as Microsoft.Office.Interop.Outlook.Application;
                    Microsoft.Office.Interop.Outlook.NameSpace nameSpace = outlookApplication.GetNamespace(ApplicationConstants.OUTLOOK_NAME_SPACE);
                    nameSpace.Logon("", "", Missing.Value, Missing.Value);
                    nameSpace = null;
                    outlookApplication.ItemSend += outlookApplication_ItemSend;
                }
                log.Info("Outlook Item Send event registered successfully.");
        }
        catch (System.Exception ex)
        {
            log.Error("Exception occurred while registering Outlook Item Send event. " + ex.Message);
        }
    }

but the same code when i launch it through Windows Form Application its working Fine. i gone through some site’s and they were saying that outlook object is not in ROT Table. what will be the solution.

asked Jun 2, 2016 at 10:58

Old, but still significant thread.

I collided with this error when tried to access Outlook data using the MS example.

Treating the error in a Try / Catch block and offering the option of newing Outlook solves the problem:

const int ERROR_HRESULT_0x800401E3_MK_E_UNAVAILABLE= -2147221021;
        Outlook.Application application = null;
        // Check whether there is an Outlook process running.
        if (Process.GetProcessesByName("OUTLOOK").Any())
        {
            try
            {
                // If so, use the GetActiveObject method to obtain the process and cast it to an Application object.
                application = Marshal.GetActiveObject("Outlook.Application") as Outlook.Application;
                }
            }
            catch (Exception ex)
            {
                //This is the branch where you can get correctly the current Outlook instance
                if (ex.HResult == ERROR_HRESULT_0x800401E3_MK_E_UNAVAILABLE)
                {
                    application = new Outlook.Application();
                }
            }
        }
        else
        {
            application = new Outlook.Application();
        }

Although the newing trick functions, no other Outlook instance is created, as Outlook behaves like a Singleton.

I only tested it with Office 365 64 bits installed.

answered Nov 15, 2020 at 15:44

you don’t need to have your application as a service to get it on the background …

if your winform work well, just put your winform in background running on the systray for instance

answered Nov 8, 2016 at 21:11

After searching on the web without success, here’s my question.

I’ve a task that i want to schedule to retrieve the attachment of an email from outlook and extract the data.
It works fine when I launch the task manually but whenever I try to launch it through a scheduled task it fails with the error :

COMException (0x800401E3): Operation unavailable (Exception from HRESULT: 0x800401E3 (MK_E_UNAVAILABLE))

It occurs when the program tries to retrieve or create an instance of Outlook as follow:

private Application GetApplicationObject()
    {

        Application application = null;

        if (Process.GetProcessesByName("OUTLOOK").Any())
        {
            application = Marshal.GetActiveObject("Outlook.Application") as Application;
        }
        else
        {
            application = new Application();
        }
        return application;
    }

I tried several ways (batch file, .exe file, parameter from a program) but they all failed.
It was launched with the same account that was use to launch the task manually.

Can someone help me ? Any help would be appreciated!
Cheers!

asked Nov 5, 2015 at 12:05