Create Exchange Meeting Programmatically

Question

Is it possible to create a meeting or appointment on someone else's Exchange 2010 account, without them needing to accept the meeting? Ideally, we want to have a delegate account, or similar strategy, to place appointments/meetings onto people's calendars. We want to bypass the normal request/accept model, and force these meetings into the calendar.

I looked at CreateItem() in the Exchange 2010 documentation, but it is unclear as to what happens once the method is executed. Does the user receive a normal invitation? We don't want that. We want a model where our system has full control over the users' calendars, without them receiving a traditional meeting invitation, and with automatic acceptance. I would prefer not to have to use VBA hacks or plugins, also.

Answer 1

I think it's possible in case of usage ApplicationImpersonation (the usage of ImpersonatedUserId). It 's important that you have to configure the Exchange first. Then you can set NetworkCredential use ImpersonatedUserId to direct access to the destination calender. See here for more information and the code example.

Answer 2

What I would do is grab a copy of MFCMapi (mfcmapi.codeplex.com), and then create a meeting request in a traditional way and send it to a couple mailboxes. Accept it in a couple, mark tentative in a couple, etc.

Take a look at the resultant calendar item created in the invitee mailbox. I expect you should be able to create the appointment and then set the necesary MAPI properties to make it appear as accepted. You can set the arbitrary properties with EWS, it's just going to take a bit of digging to figure out which ones to set. MFC Mapi is a good tool for that.

On the organizer side, you'll need to make some tweaks so it looks like everyone accepted.