Outlook 365 Group Calendars disappear

New Contributor

I have a group of users running 2 versions of outlook. 2303 Build 16227.20280 and Version 2303 Build 16227.20258 are running into the same issue where some of their group created calendars are disappearing when the launch Outlook on their Windows laptops.


I've tried updating one user to see if the issue revolves around the version.

I've tried checking the "Turn on Shared Calander improvements" but no change

I've checked auto archiving to see if that was getting involved in anyway but doesn't seem to be.

I've compacted the ost file just to be safe, I'm just not sure what could be causing this issue 


We're an O365 shop with a hybrid DC we set up emails with Azure and assign their Office licenses there. I've confirmed that the Web version of outlook isn't affected and we're using that as a work around for the time being. 


Any advice would be greatly appreciated.


10 Replies


Had the same issue, to resolve I just deleted the mail profile and recreated it.

We too have had 3 individuals have this same issue. Closing and reopening Outlook makes it appear again, however it disappears after a while too.



This is not directly related but one of our customers recently received 2303 and in their Groups section within Outlook they would either entirely disappear or the contents of the mailboxes would disappear.  Restarting Outlook and/or the computer would cause them to re-appear then disappear again.  I tried new e-mail profiles, reinstall of M365 and using the scrubbing tool/vbs scripts none of which fixed the problem.  I was able to replicate this behavior on my own computer and found that the prior version 2302 did not have this problem.  I rolled back to 2302 by switching to the Monthly Enterprise Channel.  



We encountered this issue yesterday.  I made sure Office updates were disabled. I had to do office repair twice which rolled Outlook back to 2208, no more issues.

best response confirmed by Bromastiff (New Contributor)
Microsoft published this advisory (EX540503) yesterday:

Title: Some users may be unable to view or access group calendars and email messages in the Outlook desktop client

User impact: Users may be unable to view or access Microsoft 365 group calendars and email messages in the Outlook desktop client.

More info: Affected users are part of a Microsoft 365 group and are on versions 16.0.16222.10000 or higher, including the latest February release channel. Some affected users may also notice that impact self-resolves after some time, although impact may also reoccur at a later time. These users may also be unable to perform one or more of the following actions in the Outlook desktop client:

- Add or access the group mailbox
- Add or access the group calendar
- Add, remove, or edit group members
- Changes to mail items, such as marking as read, archiving, or moving email to other folders.

Current status: We've identified that a recent service update is incorrectly triggering an indexer to remove specific values within the Outlook desktop client for some users, resulting in impact. We've developed a fix to repair this issue and are validating it within our internal test environments to ensure all affected scenarios are accounted for before proceeding.

Scope of impact: Impact is limited to a small number of users on versions 16.0.16222.10000 or higher, and are attempting to access or perform various Microsoft 365 group related actions in the Outlook desktop client.

Start time: Tuesday, March 28, 2023, 6:38 PM (11:38 PM UTC)

Root cause: A recent service update is incorrectly triggering an indexer to delete specific values within the Outlook desktop client for some users, resulting in impact.

Next update by: Wednesday, April 19, 2023, 2:00 PM (7:00 PM UTC)
I just saw this Answer on another post or something,
you do not have the permission required to create an item in this folder. Right-click the folder and click Properties to view your permissions for the folder. Ask the folder owner or your administrator to change your permissions.

I have the proper permissions needed as an Exchange admin.

Thank you.
Bende de benzer sorun var toplantı takviminde toplantılar olmasına rağmen Masaüstü Outlook uygulamasında takvimler boş görünüyor. Güncelleme önerildi fakat masaüstü outlook 365 uygulamasının sürümü 2303 den 2304 e geçtim fakat sorun hala devam ediyor. Web Browser de mailbox portalda takvimi kontrol ettiğimde takvimde toplantılar var. İlginç olan windows 11 masaüstü outlook 365 uygulamasını yeni uygulamaya geç dediğimde düzgün çalışıyor. 2303 den daha eski versiyona mı gitmeliyim? Kararlı sürüm hangisidir?


Version 2302-2303-2304 çalışmıyor. Eğer 2304 yeni uygulamaya geç dersem çalışıyor.