> My goal is to access my Microsoft Outlook Calendar from a C# program.
> If you know VB I can work with it.
>
> I started with:
>
> http://stackoverflow.com/questions/90899/net-get-all-outlook-calendar-items
>
> and wrote the following:
> ---------------------------------------------------
>
> Microsoft.Office.Interop.Outlook.Application oApp = null;
> Microsoft.Office.Interop.Outlook.NameSpace mapiNamespace = null;
> Microsoft.Office.Interop.Outlook.MAPIFolder calendarFolder = null;
>
> oApp = new Microsoft.Office.Interop.Outlook.Application();
> mapiNamespace = oApp.GetNamespace("MAPI");
> calendarFolder = mapiNamespace.GetDefaultFolder
> (Microsoft.Office.Interop.Outlook.OlDefaultFolders.olFolderCalendar);
>
> foreach (Microsoft.Office.Interop.Outlook.AppointmentItem item in
> calendarFolder.Items)
> {
> System.Console.WriteLine(item.Location);
> }
>
> ---------------------------------------------------
>
>
> Yesterday, I kept getting this exception at the start of the foreach
> loop:
>
> System.InvalidCastException was unhandled
>
> Message="Unable to cast COM object of
> type 'System.__ComObject' to interface
> type 'Microsoft.Office.Interop.Outlook.AppointmentItem'.
>
> This operation failed because the QueryInterface call on the COM
> component
> for the interface with IID '{00063033-0000-0000-C000-000000000046}'
> failed due to the following error: No such interface supported
> (Exception from HRESULT: 0x80004002 (E_NOINTERFACE))."
>
> ---------------------------------------------------
>
> This morning, when I logged in, the program ran perfectly.
>
> This afternoon, I am getting the same exception.
>
> What is unique or special about COM that I need to know in order to
> avoid these exceptions?
>
> Is there some sort of system configuration that I need to turn on?
> Something in the registry?
>
> Thanks.