Exchange Calendar Events for all users in my organization - exchange-server

Is there a way to subscribe to all NEW calendar entries create by all users in my organization? Basically, whenever anyone in my organization creates a meeting invite, my app needs to be notified.
Our app needs this to work for both Exchange Online and On-premise.

Is there a way to subscribe to all NEW calendar entries create by all users in my organization?
No Subscriptions and always in the context of a Mailbox or Mailbox Folder (you need to consider your mailboxes will be spread across different servers in different data-centers)
As a workaround you could create a Transport Rule that catches any Meeting invitations and redirect them to a particular mailbox. Then just subscribe to events on that mailbox.

Related

Send calendar event invitations on behalf of a user with Microsoft Graph

I have a web app that allows receptionists to create calendar events on Outlook/Office365. To manage the events I use Microsoft Graph. The app sends the Graph requests under his own identity, because I need it to have no user interaction for logging in, so it uses Client_ID and Client_Secret with administrator rights to do everything. I can create events on the calendars of any user in the organization, which kinda works like creating an event "On behalf of", but there's a problem. When you create an event in someone else's calendar, Outlook will send the invitations as the calendar's owner, and this means that if the owner doesn't have permission to send messages to a mailbox (for example, a room mailbox), the invitation will never arrive. I need it to send the invitations from another user account (the receptionist that creates the event), like Office 365 does when you create an event on a shared calendar. Is that possible? Or is there any workaround to accomplish what I need?

Correlating meetings in Outlook calendar on different computers

If you send a meeting request to someone using Outlook, no user or custom MAPI properties will go into the meeting created the attendee's Outlook calendar.
I am looking for a way to correlate meetings that belong together across multiple attendee's computer.
I have found that the "Conversation ID" or the first 44 characters of the "Conversation Index" property are the same across all attendees computer, ONLY if all the attendees are on the same MS Exchange server. This does not work for different exchange servers or local computer only calendars.
Is there any reliable way that I can do this?
Appointment id (AppointmentItem.GlobalAppointmentID) will be the same for all instances of the appointment.

Exchange EWS ErrorCalendarIsNotOrganizer despite being the organizer

I'm trying to cancel a meeting I created by using an EWS XML CreateItem request (against a 2013 server):
<ns2:CreateItem MessageDisposition="SendAndSaveCopy"><ns2:Items>
<ns1:CancelCalendarItem>
<ns1:ReferenceItemId Id="AAMkA...." ChangeKey="DwAAA..."/>
</ns1:CancelCalendarItem>
</ns2:Items></ns2:CreateItem>
So far so good, however Outlook denies me access with the ResponseCode "ErrorCalendarIsNotOrganizer" / "User must be an organizer for CancelCalendarItem action".
A look in the event detail by using GetItem with BaseShape=ALL_PROPERTIES reveals that the account I use is set as Organizer, however at the same time:
the IsOrganizer field is set to false
in EffectiveRights the fields Read, Modify and Delete are true.
I can delete the appointment lateron using a DeleteItem request and it works, however it only removes the appointment from the room's calendar but not from the mailboxes of the attendees.
What causes this? There is no impersonation in use, only the service account I use has delegation access to every room mailbox (to be able to see all appointments).
I can delete the appointment lateron using a DeleteItem request and it works, however it only removes the appointment from the room's calendar but not from the mailboxes of the attendees.
It sounds like your accessing the appointment in the Room Mailboxes calendar ? this is why even if your using the account that is the organizer of that appointment the isOrganizer will return as false because this property is only true on the copy of the Appointment in the Organizers calendar. To correctly cancel the meeting you need to do that on the calendar of the Organizer (not the rooms or any attendee instance of the meeting). This will still only delete the appointment in the organizer calendar and send cancellation messages to the attendees.
An important point is that all instances of the meeting stored in the Attendees and Meeting Room calendars are separate Exchange Store items with no direct link. So deleting the organizer instance (or any attendee instance) has no affect on the other attendees instances these must be processed separately by the attendees themselves based on the cancellation message that is received.

End Event on Room Resource calendar

The problem that I face: I currently use a product that displays calendar items on an iPad outside of conference rooms. I have all the room resources set up and everything works brilliantly except if I try to end the event early from this display.
The reason it doesn't end: When User A schedules a meeting and adds the room Conference Room as a resource, and Conference Room accepts, the meeting is still owned by the organizer, or in this case User A. Because of this, the room itself can not edit times on an event, only the organizer can.
The question: Is there any way, to have the Room auto accept the meeting, and also be able to edit the event?
Please note, I have tried this with Exchange 2007, Exchange 2010, Exchange 2013, and Office 365. The servers have been both on-premises and hosted.
No the only valid editor of a Meeting is the organizer for the reason that each copy of the meeting stored in the Attendees mailboxes is a separate item in the Exchange Mailstore. Eg Even if the Organizer modifies the appointment and doesn't send out Meeting updates the changes they make won't show on the attendees (or Room Mailbox) calendar until the updates are sent and accepted. This is fundamental to the way in which Appointments work if you need to change a meeting for some reason you may want to look at impersonating the Owner of the Appointment in EWS. The one thing the Room mailbox (or any attendee) could do is propose a new meeting time which would be a separate message that would sent back to the Organizer who then once they accepted would send out a normal Meeting update to all attendees.
Cheers
Glen

Use exchange web services managed API to subscribe to notification when appointment has started

How can I subscribe to a notification that will trigger every time that an appointment has started?
This is not possible, since Exchange does care about appointments in user mailbox. For the store, it's just an element with a bunch of properties.
What you can do is create a service which checks a users mailbox, retrieves all appointments and triggers an event once an appointment has started. Additionally, you can subscribe for notifications so that your application is informed by the Exchange server when an item in the users mailbox changes.

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