Mailbox owner cannot accept calendar invites in Outlook 2016 Windows desktop app

Copper Contributor

example of delegate permissionsexample of delegate permissions

I have a Sr. VP who for some reason cannot accept calendar invitations from either within the organization or from outside people in his Outlook 2016 desktop app.  He can accept them in OWA or from his iPhone.  I have installed his profile on 3 different computers running Windows 10 Pro and Windows 7 Pro with the same result.  I have contacted Office 365 support through my administrator dashboard and while I received a call back, the engineer has not been able to help me.


I feel that it is some sort of a preference that is set on this employee's ID in the cloud, but our main admin doesn't think so.  I did notice that this VP's assistant is a delegate with editor rights in delegations, but she is also showing up as an owner of our VP's mailbox on the server too.  Could this be a problem?  I have uploaded an example of the greyed out rights the delegate has now.


Have any of you had this issue before?  Any assistance would be greatly appreciated.

2 Replies

What exactly happens when he tries to accept a request via Outlook? Or do you mean the request never appear in Outlook? Did you try running Outlook in safe mode, just to make sure some add-in is not messing up things? I would also suggest trying on different network (Wi-Fi or home PC for example), see if it makes a difference.


The option you've shown above can certainly have an effect, however it will apply across all modalities, now just Outlook. Still, I guess you can try removing the delegates then re-adding them and adjusting the setting accordingly.


No one in our organization can get Outlook to go into safe mode.  Something changed a few months ago because we used to be able to access safe mode, but now it just hangs our client. 


I removed the delegates from this person's mailbox, then removed Office 365 from the computer completely and deleted any Office or Outlook folders from the computer.  I then re-installed Office again and then without having any delegates, I then tried to accept a test meeting that I had sent.  The same thing happened, it said on this employee's meeting request that no response was required and none of the Accept, Decline or Tentative buttons were showing.


When I went to add the delegates back in Outlook in the Delegates area, I received a message that said, "The Delegates settings were not saved correctly.  Cannot activate free/busy information".


I tried the information in the attached PDF, but couldn't find the field stipulated here either.


Thank you for your reply,