(Outlook) Duplicate Meeting on Delegates Calendar

Copper Contributor

Does anyone else have an issue where an executive admin is seeing duplicate meetings for the same time on the executives calendar?  We saw this issue months ago and it has returned. 

3 Replies

Hi @ExchAdmin90,

can you provide a bit more context?

  • Are there any users having delegate or full permission to that mailbox?
  • Who is the organizer of the duplicate meetings? 
    • The primary user of the mailbox?
    • A delegate to the mailbox?
    • Someone with write-permission to the mailbox and the calendar but not a proper delegate?
  • Does the owner of the mailbox
    • use mobile devices?
    • use multiple Outlook clients?
  • Have you compared the duplicate entries using MFCMapi?



@Thomas Stensitzki 

  • The admins have full access to the execs calendar and mailbox (if that was your question)
  • Organizer of the duplicate meeting is a general user in the company that sends a meeting invite to the executive.
  • Owner of the mailbox uses mobile devices and possibly desktop client. (iPad, iPhone, Desktop)
  • I have not compared using MFCMAPI, i can navigate the software but wouldn't know how to look for specific meetings with it to compare. 


This is happening to several admins that have delegate access to execs mailboxes. 


The "full access" permission question was not related to admin users but to other team/department/company users. 

Historically, duplicate meetings are created due to very different issues, e.g., (in your example)

  • The executive has a delegate who receives invites for the executive user and confirms attendance, but the executive user himself confirms for a second time.
  • The executive confirms an invite multiple times from different devices, and the devices cannot transmit the updated invite, e.g., hibernating a computer with Outlook desktop still open (one of my favorite issues).

Therefore, it is essential to understand how the mailbox is accessed and by whom.


Some other questions:

  • What happens when the organizer sends a meeting update? Which meeting gets updated?
  • Is the duplicate a single meeting, a meeting series, or a single updated meeting as part of a meeting series?

Another tool you can use is EWS Editor.

And yes, there are many moving parts regarding meeting invites.