Hi Hal Trask,
That's a very good question, thank you for asking.
As far as I know, Exchange supports MAPI, WebDav and Web Services as means to communicate with third party applications. We have considered all of them in order to choose the best one for the provider.
We have ruled out MAPI, as it is a 16/32-bit only native component and running it on a 64-bit server would have been troublesome. Initially WebDav looked very promising, as it is not Exchange-specific, but eventually we ruled it out, as it was ridicilously complex when dealing with recurring appointments.
So, we have decided on using Web Services, as they seem to be the officially supported means of communicating with exchange. Retrofitting the provider to use the other mechanisms would be very difficult at this point.
We will be happy to provide additional examples. Can you please tell us what scenarios might be of interest to you?
the Telerik team
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