There is something wrong with classic outlook calendar sharing.

Question

There is something wrong with classic outlook calendar sharing.

a. darcy 15

My wife and I have shared outlook calendar for years. She use IOS and I use Chrome OS and Android. On June 13, 2026 my wife could no long see my calendar on her device. We found another user with the same problem. He had to create another outlook mail account and share that calendar with his partner. There is something wrong with classic outlook calendar sharing.

Personal Outlook accounts (not Microsoft 365)
Calendar sharing worked for years, stopped June 13, 2026
Devices: ChromeOS, Android, iOS
Tried deleting and re-adding sharing — didn't work
Another user reported the same issue starting the same date
The only workaround found so far is creating a brand new account

MikeSch 10 Reputation points

2026-06-17T21:25:53.9733333+00:00

Same problem with my family. I created a shared calendar that my family has been using for years. As of yesterday, or perhaps the day before (June 15th/16th) we noticed it was no longer there. Calendar is gone from each of my family on outlook for android, outlook.exe, outlook.com. As the shared calendar owner I tried removing user and readding, and that allowed them to see the calendar again, but they can no longer edit, even though permissions are set properly.
FF 5 Reputation points

2026-06-18T22:10:32.4833333+00:00

Same here... all MS outlook accounts no longer sharing with each other. Looking at the configuration all sharing email addresses are still there on the sharing side but the viewer no longer list the calendar at all. Must be something wrong. Do not use the classic outlook version. Use outlook.com, new outlook, and Android outlook. None of them work starting this last week, not sure exactly which day. Did not change anything, sharing disappeared.
Hornblower409 15,520 Reputation points

2026-06-18T22:27:41.1+00:00

Appears to be an on-going problem with the Microsoft infrastructure. No official Service Bulletin from Microsoft that I have seen.

Shared Outlook Calendar has disappeared
https://learn.microsoft.com/en-us/answers/questions/5922100/shared-outlook-calendar-has-disappeared

Answer recommended by moderator

Hornblower409 15,520

@a. darcy said

Another user reported the same issue starting the same date

If you are seeing the same problem as described in these other reports:

https://learn.microsoft.com/en-us/answers/questions/5917173/shared-calendar-only-showing-busy-or-free-despite
https://learn.microsoft.com/en-in/answers/questions/5917185/shared-outlook-com-calendar-doesnt-show-event-deta
https://learn.microsoft.com/en-us/answers/questions/5920057/calender-sharing-not-working-like-it-did

Looks like it's a Microsoft Bug.

See the Answer by "Victor1-V Jun 13, 2026" in
https://learn.microsoft.com/en-us/answers/questions/5917173/shared-calendar-only-showing-busy-or-free-despite

Since this is affecting multiple users and also happens in Outlook.com on the web, it may not be caused by a local app cache or an individual device setting.

Sconn90 0 Reputation points

2026-06-16T19:28:48.02+00:00

We had the same issue. Although Outlook desktop shows the ability to update shared calendar users and permissions, it doesn't actually work. The clue was when the I opened the email with a button to "Accept" the shared calendar invitation in Outlook desktop, it opened a browser tab for Outlook on the web. Stupid design choice by the developers, but it gave me the idea.

I used Outlook on the web to update the shared calendar permissions, and suddenly everything works again.

3 additional answers

Your answer

MikeSch 10 Reputation points

2026-06-17T21:25:53.9733333+00:00

Same problem with my family. I created a shared calendar that my family has been using for years. As of yesterday, or perhaps the day before (June 15th/16th) we noticed it was no longer there. Calendar is gone from each of my family on outlook for android, outlook.exe, outlook.com. As the shared calendar owner I tried removing user and readding, and that allowed them to see the calendar again, but they can no longer edit, even though permissions are set properly.
FF 5 Reputation points

2026-06-18T22:10:32.4833333+00:00

Same here... all MS outlook accounts no longer sharing with each other. Looking at the configuration all sharing email addresses are still there on the sharing side but the viewer no longer list the calendar at all. Must be something wrong. Do not use the classic outlook version. Use outlook.com, new outlook, and Android outlook. None of them work starting this last week, not sure exactly which day. Did not change anything, sharing disappeared.
Hornblower409 15,520 Reputation points

2026-06-18T22:27:41.1+00:00

Appears to be an on-going problem with the Microsoft infrastructure. No official Service Bulletin from Microsoft that I have seen.

Shared Outlook Calendar has disappeared
https://learn.microsoft.com/en-us/answers/questions/5922100/shared-outlook-calendar-has-disappeared
Sconn90 0 Reputation points

2026-06-16T19:28:48.02+00:00

We had the same issue. Although Outlook desktop shows the ability to update shared calendar users and permissions, it doesn't actually work. The clue was when the I opened the email with a button to "Accept" the shared calendar invitation in Outlook desktop, it opened a browser tab for Outlook on the web. Stupid design choice by the developers, but it gave me the idea.

I used Outlook on the web to update the shared calendar permissions, and suddenly everything works again.

Answer 1

Brian Tillman 27,125 Independent Advisor

Sorry I didn't get back to you quickly enough. I had to leave town for this past week and I didn't see your replies soon enough.

It looks like you received some good help in my stead. Typically, accessing an account whose domain is @hotmail.com using classic Outlook, you'll have an Exchange account. So, as you found out, a calendar not working correctly would be Microsoft's fault, since it worked previously. Hopefully, the problem has been resolved.

0 comments

Answer 2

Brian Tillman 27,125 Independent Advisor

Hi. I'm Brian and I'll try to help.

This forum is dedicated to using Outlook.com with a web browser. Classic Outlook is covered in a different forum.

Calendar sharing is done via the mail provider. You say you're not using Outlook.com (i.e., you said "personal Outlook accounts, not Microsoft 365.") Who is your mail provider and what type of account (POP, IMAP, Exchange) are you using in classic Outlook? What changed on your computer or with your account between when it worked and now? Providing complete details always gets you better responses.

a. darcy 15 Reputation points

2026-06-14T23:11:05.1633333+00:00

I am using ******@hotmail.com - I don't know how to ID the provider. My wife uses the same, a ******@hotmail.com address. Are these Exchange? I believe we use classic outlook. I don't think we changed anything - same devices, no changes to permissions, nothing.

Answer 3

Calendar sharing issues starting suddenly across multiple devices and accounts strongly suggest a backend change in the Outlook.com / classic Outlook calendar sharing platform rather than a local configuration problem.

From the available information:

Classic Outlook / legacy sharing model is known to have issues and has been undergoing changes and improvements over time. Microsoft has a newer sharing model that works best when invitations are accepted from Outlook on the web, iOS, Android, or Windows 10 Calendar, and when calendars are on the “new model.” Older/legacy shares can stop syncing correctly across clients.
For Outlook.com and personal accounts, mobile clients (iOS/Android) only reliably show shared calendars that were accepted recently from supported clients (web, iOS, Android, Windows 10 Calendar). Older shares can effectively “age out” or break and stop appearing or syncing on mobile.
When a shared calendar stops appearing on mobile, Microsoft’s documented remediation is:
- Have the owner re-share the calendar.
- Accept the new sharing invitation from Outlook on the web, iOS, Android, or Windows 10 Calendar (not from classic desktop Outlook).
- Alternatively, search for and add the shared calendar directly in the Outlook mobile app using the + button in Calendar view.

Given that re-sharing already failed in this case, the most likely explanation is a backend change that affected legacy/"classic" shares for Outlook.com calendars around that date. The workaround another user found (creating a new Outlook.com account and sharing from there) effectively forces creation of a brand-new calendar and share on the new model, which aligns with Microsoft’s direction for calendar sharing.

Actionable steps that align with documented behavior:

Ensure the calendar is shared using the current model
- From the owner’s Outlook.com (web): share the calendar again to the partner’s Outlook.com address.
- Make sure the permission level is at least “Can view all details” or similar, not restricted to free/busy only.
Accept the share from a supported client
- On the recipient side, open the new sharing invitation in:
  - Outlook on the web, or
  - Outlook for iOS, or
  - Outlook for Android.
- Accept the invitation there (not in classic Outlook desktop).
If the calendar still does not appear on mobile
- On iOS/Android, in Outlook:
  - Go to Calendar view.
  - Use the + button/menu to search for the owner’s calendar and add it directly.
- This is specifically documented as a way to surface shared calendars that should be visible on mobile.
If none of the above works
- The behavior is consistent with a service-side regression affecting legacy shares. In that case, the only currently known effective workaround (based on similar user reports) is:
  - Create a new Outlook.com calendar identity (or a new primary account) and set up sharing fresh, ensuring invitations are accepted from web/iOS/Android so they are on the new sharing model.

There is no documented client-side fix (settings, cache clearing, etc.) for a scenario where legacy Outlook.com shared calendars stop syncing across all devices at the same time. The pattern and Microsoft’s own guidance around “recently accepted” shares and the new sharing model indicate this is a service/model issue with classic sharing, not a misconfiguration on the devices.

References: