Unable to cast COM object of type 'System.__ComObject'

Question

enter image description here

enter image description here When I am a casting below code then i got an error

Code :

string subject = ((Microsoft.Office.Interop.Outlook.MailItem)myInbox.Items[temp])
    .Subject.ToString();

Unable to cast COM object of type 'System.__ComObject' to interface type 'Microsoft.Office.Interop.Outlook.MailItem'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{00063034-0000-0000-C000-000000000046}' failed due to the following error: No such interface supported (Exception from HRESULT: 0x80004002 (E_NOINTERFACE)).

Can you try to get the actual com type of myInbox.Items[temp] by checking [this](http://stackoverflow.com/questions/1429548/how-to-get-type-of-com-object) — Oguz Ozgul, Nov 02 '15 at 10:32
[System.RuntimeType] = {Name = "__ComObject" FullName = "System.__ComObject"} means its change the runtime type system._ComObject — ketannsolanki solanki, Nov 02 '15 at 10:47
The inbox can contain more than just mail items. Use the `as` operator to skip the ones you don't like. — Hans Passant, Nov 02 '15 at 11:16
no inbox not contain more mail items the mail which have auto response that type of mail gives the error you can see the mail which gives the error in highlighted by red box you can see in the attachment. — ketannsolanki solanki, Nov 02 '15 at 11:36
Before you go any further: what are you trying to do? I see you're writing an ASPX page. Please note that that code will **not** interact with the visitor's Outlook. — CodeCaster, Nov 02 '15 at 11:45
Yes, that's exactly what Hans said - it's not a `MailItem`. You need to skip the inbox items that aren't `MailItem`s. — Luaan, Nov 02 '15 at 12:42
Possible duplicate of [Unable to cast COM object - Microsoft outlook & C#](https://stackoverflow.com/questions/4656360/unable-to-cast-com-object-microsoft-outlook-c-sharp) — Gokul, Jun 03 '17 at 20:57

score 3 · Answer 1 · answered Nov 02 '15 at 12:42

You need to check the item type first. Outlook folders may contain various types of items:

Object selObject = this.Application.ActiveExplorer().Selection[1];
        if (selObject is Outlook.MailItem)
        {
            Outlook.MailItem mailItem =
                (selObject as Outlook.MailItem);
            itemMessage = "The item is an e-mail message." +
                " The subject is " + mailItem.Subject + ".";
            mailItem.Display(false);
        }
        else if (selObject is Outlook.ContactItem)
        {
            Outlook.ContactItem contactItem =
                (selObject as Outlook.ContactItem);
            itemMessage = "The item is a contact." +
                " The full name is " + contactItem.Subject + ".";
            contactItem.Display(false);
        }
        else if (selObject is Outlook.AppointmentItem)
        {
            Outlook.AppointmentItem apptItem =
                (selObject as Outlook.AppointmentItem);
            itemMessage = "The item is an appointment." +
                " The subject is " + apptItem.Subject + ".";
        }
        else if (selObject is Outlook.TaskItem)
        {
            Outlook.TaskItem taskItem =
                (selObject as Outlook.TaskItem);
            itemMessage = "The item is a task. The body is "
                + taskItem.Body + ".";
        }
        else if (selObject is Outlook.MeetingItem)
        {
            Outlook.MeetingItem meetingItem =
                (selObject as Outlook.MeetingItem);
            itemMessage = "The item is a meeting item. " +
                 "The subject is " + meetingItem.Subject + ".";
        }

See How to: Programmatically Determine the Current Outlook Item for more information.

I have request read receipt type outlook mail in my inbox and i want to read that particular mail from c# — ketannsolanki solanki, Nov 02 '15 at 17:03

score 0 · Answer 2 · edited Nov 24 '15 at 09:34

0

string subject = myInbox.Items[temp])
    .Subject.ToString();

There is no need to cast frist check that myinbox object have subject property in not string then you need to cast it if it is string formate then don't need to cast it.

edited Nov 24 '15 at 09:34

Kamil Budziewski

22,699
14
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answered Nov 24 '15 at 09:04

ketannsolanki solanki

11
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Unable to cast COM object of type 'System.__ComObject'

2 Answers2