Up to now, the following line worked.
var comObject = Activator.CreateInstance(
Type.GetTypeFromProgID("Outlook.Application"))
Since "the new Outlook" is turned on, that line does not return and just waits for something and hangs arround forever. Any ideas?
The new Outlook (Monarch) is an app completely different from the classic desktop Outlook and does not expose any API besides Web (JS) addins. There is nothing like the Outlook Object Model.
Keep in mind that Monarch (at least in its current version) is a replacement for Windows Mail and Windows Calendar, not desktop Outlook, which is still fully supported.