Windows 10: Calendar invitation is re-sending out meeting invites with some regularity

Mailbox Calendar invitation is re-sending out meeting invites with some regularity ~4 or 5 per day, going back some weeks. In most cases, none of the meeting details have changed time, location, attendees and the admins also mailbox delegates say they haven’t touched the invite. Going to external addresses which is especially problematic.On premise: Exchange 2013No Rules added.

:)

 

Calendar App does NOT send meeting invites

I have attempted to generate meetings using my Windows Phone 8 Calendar app. However, the app does NOT send the meeting invites to the identified users. When I go to my Win 8 calendar app, the calendar entry exists and shows the invitee's with "no reply"
in the response section. If I then use the Win 8.1 calendar app invite section and <send> the message the invite goes out.

What's the deal with the Win Phone 8 calendar app that it does not send meeting invites? Why?????

 

Calendar meeting invite requests

I set up a meeting in my calendar and invite others as per normal. It appears in my calendar, and says it has been sent to invitees. However the invitees say nothing comes up in their calendar as an invite. So I cancel the meeting, and then the invitees
say that the cancellation has come up in their calendar for a meeting that never appeared in the first place. Does anyone know how to fix this on my Surface? Have not had any problems until a few weeks ago.

 

Cannot Invite People to Calendar Meetings

• It defaults to the Outlook calendar. Why wouldn't the outlook calendar let me invite someone? The Calendar app is supposed to aggregate all our calendars so when we set up an event using the app, it should let us send invite to anyone without having to
  choose the Yahoo or Google calendars when we first set up the event.
  
• Why can't I go into an event and change the calendar it's assigned to at a later time? If I set up an event under the outlook calendar using this app, and realize later on that I can't invite anyone, I should be able to change it from the outlook calendar
  to the yahoo calendar without having to set up a new event.