Recurring "Something went wrong" Calendar Event Creation Error

Question

Recurring "Something went wrong" Calendar Event Creation Error

Ali Asfar 5

Environment:

OS: macOS

Clients Affected: Microsoft Teams (Desktop for Mac), Teams Web App, and Outlook Web

Account Type: Office 365 / Exchange Online

Issue Description: I am repeatedly unable to create new calendar events or meetings. When attempting to save an event, I receive a popup error stating: "Something went wrong. We couldn't send your calendar event. Waiting a bit might help. Keep your calendar event open to try again later." Signing out and signing back into the application temporarily resolves the issue, but the error consistently returns after a short period.

Key Scenarios & Symptoms:

Cross-Platform Failure: The exact same error occurs on the macOS desktop app AND when using the web browser versions of Teams and Outlook.

Persistence: The issue persists even after comprehensive local cache and credential clearing.

Troubleshooting Steps Already Taken: To isolate the issue, I have already completed the following steps with no permanent success:

App Reinstallation: Uninstalled and reinstalled the Microsoft Teams application on macOS.

Deep Cache Clear (macOS): Completely removed local cache directories via Terminal (~/Library/Group Containers/UBF8T346G9.com.microsoft.teams, ~/Library/Containers/com.microsoft.teams2, and Classic Teams App Support folders).

Credential Purge: Deleted all Microsoft Teams, ADAL (Active Directory Authentication Library), and Microsoft Office credential entries from the macOS Keychain.

Web Isolation Test: Verified the issue occurs on teams.microsoft.com and outlook.office.com, ruling out a localized macOS client or OS cache corruption.

Time Zone & Regional Sync: Verified that the macOS System Date & Time settings (Time Zone and 12h/24h formatting) exactly match the Time Zone and Regional settings configured in the Outlook Web App (OWA) settings.

Work Hours Reset: Toggled and re-saved the "Work hours and location" in OWA to force an update to the server parameters.
One Account Issue across organization: Only one account is facing this issue across the entire organization.

Request: Given that this issue occurs consistently across the desktop application and the web browser, Screenshot 2026-05-14 at 11.16.45 AM (1)

could you please help identify what is causing this bug and provide the appropriate solutions to resolve it?

Maya 0

Because the issue reproduces across Teams Desktop, Teams Web, and Outlook Web for only one user account, this strongly suggests the problem is server-side at the Exchange Online mailbox/calendar level rather than a macOS client or Teams cache issue.

Since local cache resets, credential removal, browser isolation, reinstallations, and timezone validation have already been performed, I would investigate the following mailbox-side causes:

Corrupted calendar items or hidden calendar metadata

Run mailbox calendar diagnostics.

Check for malformed recurring meetings or hidden sync conflicts.

Use:

- `Outlook.exe /cleanreminders` (if Windows testing is available)

      - Microsoft Support and Recovery Assistant (SaRA)

            - Exchange Online calendar diagnostic tools

            Exchange Online mailbox corruption

               - Run:

                     - `Get-MailboxFolderStatistics`

                           - `New-MailboxRepairRequest` targeting Calendar-related corruption.

                           Delegation or permission corruption

                              - Review mailbox delegates, shared calendars, and Send-As permissions.

                                 - Remove/re-add delegates temporarily.

                                 EWS / Graph API failures

                                    - Since Teams and OWA both fail, there may be backend API failures tied to the mailbox object itself.

                                       - Check Entra sign-in logs and Exchange Online service health.

                                       Problematic recurring meetings

                                          - Corrupted recurring meetings can continuously poison calendar sync.

                                             - Try creating events in a brand-new secondary calendar instead of the primary calendar.

                                             Licensing / mailbox provisioning inconsistencies

                                                - Reconfirm Exchange Online licensing and mailbox provisioning state.

                                                   - Sometimes removing/reapplying the Exchange Online license can refresh backend provisioning.

At this point, because the problem is isolated to a single mailbox but affects all clients/platforms, I would recommend opening a Microsoft 365 support ticket and providing:

Correlation IDs
Exact timestamps
HAR traces from OWA
Teams logs
Exchange mailbox diagnostics

This appears much more likely to be an Exchange Online calendar backend issue than a Teams/macOS issue.Because the issue reproduces across Teams Desktop, Teams Web, and Outlook Web for only one user account, this strongly suggests the problem is server-side at the Exchange Online mailbox/calendar level rather than a macOS client or Teams cache issue.

Since local cache resets, credential removal, browser isolation, reinstallations, and timezone validation have already been performed, I would investigate the following mailbox-side causes:

Corrupted calendar items or hidden calendar metadata

Run mailbox calendar diagnostics.

Check for malformed recurring meetings or hidden sync conflicts.

Use:

- `Outlook.exe /cleanreminders` (if Windows testing is available)

      - Microsoft Support and Recovery Assistant (SaRA)

            - Exchange Online calendar diagnostic tools

            Exchange Online mailbox corruption

               - Run: 

                     - `Get-MailboxFolderStatistics`

                           - `New-MailboxRepairRequest` targeting Calendar-related corruption.

                           Delegation or permission corruption

                              - Review mailbox delegates, shared calendars, and Send-As permissions.

                                 - Remove/re-add delegates temporarily.

                                 EWS / Graph API failures

                                    - Since Teams and OWA both fail, there may be backend API failures tied to the mailbox object itself.

                                       - Check Entra sign-in logs and Exchange Online service health.

                                       Problematic recurring meetings

                                          - Corrupted recurring meetings can continuously poison calendar sync.

                                             - Try creating events in a brand-new secondary calendar instead of the primary calendar.

                                             Licensing / mailbox provisioning inconsistencies

                                                - Reconfirm Exchange Online licensing and mailbox provisioning state.

                                                   - Sometimes removing/reapplying the Exchange Online license can refresh backend provisioning.

At this point, because the problem is isolated to a single mailbox but affects all clients/platforms, I would recommend opening a Microsoft 365 support ticket and providing:

Correlation IDs
Exact timestamps
HAR traces from OWA
Teams logs
Exchange mailbox diagnostics

This appears much more likely to be an Exchange Online calendar backend issue than a Teams/macOS issue. Good 🤞 Luck

Ali Asfar 5 Reputation points

2026-05-18T11:27:27.9233333+00:00

The "Teams Meeting" Toggle Trigger: I have isolated the exact trigger for the error.

If I create a standard calendar event with the "Teams meeting" toggle OFF, the event is created and saved successfully without any errors.

If I toggle "Teams meeting" ON to add an online meeting link, the creation immediately fails with the "Something went wrong" error.

Update the "Request" section to this:

Request: Given that standard calendar events save perfectly, but events with the "Teams meeting" toggle enabled fail consistently across both the desktop app and the web browser.

Could you please help identify why my account is failing to generate and attach Teams meeting links to calendar events, and provide the appropriate solutions to resolve this backend sync issue?
Hornblower409 14,600 Reputation points

2026-05-19T12:14:17.0966667+00:00

@Maya said

Since local cache resets, credential removal, browser isolation,
...

Since local cache resets, credential removal, browser isolation,
...

Your comment has the same text duplicated. This is a common problem when doing a copy/paste from an external source (e.g. AI Chat Answer). Please edit your comment to remove the redundancies.
Anonymous

2026-05-20T05:13:44.5033333+00:00

I need additional information about the questions.
Hornblower409 14,600 Reputation points

2026-05-20T05:30:01.97+00:00

@Anonymous said

I need additional information about the questions

I'm sorry, but it's not clear - Who exactly are you replying to? What questions are you referring to?
AndrewD.Lawlor 0 Reputation points

2026-06-05T13:37:36.8466667+00:00

I have a windows user with the same issue when trying to add a teams meeting to the calendar. A standard event saves fine.

The same error message is presented using new outlook, webmail, or teams client.

The user can create teams meetings using Outlook classic.

So far, it's one person out of 15,000 reporting this particular problem.
Hornblower409 14,600 Reputation points

2026-06-05T16:15:39.56+00:00

@AndrewD.Lawlor said

So far, it's one person out of 15,000 reporting this particular problem
The same error message is presented using new outlook, webmail, or teams client.

That just seems to scream "Corrupted Tenant". Give them a new account? Bring in Microsoft Support to look at the existing tenant?

3 answers

Your answer

Ali Asfar 5 Reputation points

2026-05-18T11:27:27.9233333+00:00

The "Teams Meeting" Toggle Trigger: I have isolated the exact trigger for the error.

If I create a standard calendar event with the "Teams meeting" toggle OFF, the event is created and saved successfully without any errors.

If I toggle "Teams meeting" ON to add an online meeting link, the creation immediately fails with the "Something went wrong" error.

Update the "Request" section to this:

Request: Given that standard calendar events save perfectly, but events with the "Teams meeting" toggle enabled fail consistently across both the desktop app and the web browser.

Could you please help identify why my account is failing to generate and attach Teams meeting links to calendar events, and provide the appropriate solutions to resolve this backend sync issue?
Hornblower409 14,600 Reputation points

2026-05-19T12:14:17.0966667+00:00

@Maya said

Since local cache resets, credential removal, browser isolation,
...

Since local cache resets, credential removal, browser isolation,
...

Your comment has the same text duplicated. This is a common problem when doing a copy/paste from an external source (e.g. AI Chat Answer). Please edit your comment to remove the redundancies.
Anonymous

2026-05-20T05:13:44.5033333+00:00

I need additional information about the questions.
Hornblower409 14,600 Reputation points

2026-05-20T05:30:01.97+00:00

@Anonymous said

I need additional information about the questions

I'm sorry, but it's not clear - Who exactly are you replying to? What questions are you referring to?
AndrewD.Lawlor 0 Reputation points

2026-06-05T13:37:36.8466667+00:00

I have a windows user with the same issue when trying to add a teams meeting to the calendar. A standard event saves fine.

The same error message is presented using new outlook, webmail, or teams client.

The user can create teams meetings using Outlook classic.

So far, it's one person out of 15,000 reporting this particular problem.
Hornblower409 14,600 Reputation points

2026-06-05T16:15:39.56+00:00

@AndrewD.Lawlor said

So far, it's one person out of 15,000 reporting this particular problem
The same error message is presented using new outlook, webmail, or teams client.

That just seems to scream "Corrupted Tenant". Give them a new account? Bring in Microsoft Support to look at the existing tenant?

Answer 1

The context only contains one closely related case of a similar Outlook calendar error where new events could not be sent. In that case, the issue was resolved simply by restarting the PC; no deeper server-side or configuration cause was documented.

Because the problem in this scenario reproduces across Teams desktop, Teams web, and Outlook web, and persists after cache clearing and client reinstalls, it is most likely a server-side or account-specific issue in Exchange Online rather than a macOS client problem. The provided context does not include any additional supported root-cause analysis or remediation steps beyond the single case where a restart resolved the issue.

Based on the available information, the only supported guidance from the context is:

Restart the device and test creating a new calendar event again.
If the issue persists, escalate to Microsoft Support with full details (account, tenant, and exact error) so they can investigate the mailbox and service-side configuration, since this appears to be an isolated account issue.

References:

Unable to send new calendar events in Outlook. - Microsoft Q&A

Answer 2

Ana Le 2,345 Independent Advisor

Hi @Ali Asfar,

Thank you for the detailed information and for sharing all the troubleshooting already completed.

Since the issue occurs across both Teams and Outlook on web and desktop, and only affects a single account, we would first like to narrow down whether the issue is related specifically to the affected calendar folder, recurring meeting settings, or the mailbox configuration itself.

Could you please help test the following:

1/ Try creating:

a normal single meeting
a recurring meeting
a meeting without attendees

and let me know which scenarios fail.

2/ In Outlook Web App, create a brand-new calendar and test creating events there: This helps check whether the issue is isolated to the default Calendar folder.

3/ If Outlook desktop for Mac is available, please test creating calendar events from there as well and confirm whether the same error appears.

You may also review these similar Microsoft discussions for reference:

I am unable to send new meeting invitation from my outlook web app on Mac. - Microsoft Q&A

I am unable to send any calendar event from my Outlook . - Microsoft Q&A

Please share the test result when available, and we’ll continue checking from there.

Ali Asfar 5 Reputation points

2026-05-18T11:20:46.47+00:00

The "Teams Meeting" Toggle Trigger: I have isolated the exact trigger for the error.

If I create a standard calendar event with the "Teams meeting" toggle OFF, the event is created and saved successfully without any errors.

If I toggle "Teams meeting" ON to add an online meeting link, the creation immediately fails with the "Something went wrong" error.

Update the "Request" section to this:

Request: Given that standard calendar events save perfectly, but events with the "Teams meeting" toggle enabled fail consistently across both the desktop app and the web browser.

Could you please help identify why my account is failing to generate and attach Teams meeting links to calendar events, and provide the appropriate solutions to resolve this backend sync issue?
Ali Asfar 5 Reputation points

2026-05-18T11:23:20.9166667+00:00

To answer your questions yes same error in single, recurring and meeting with no attandees. The outlook desktop app is also facing the same issue.
Ana Le 2,345 Reputation points Independent Advisor

2026-05-20T05:11:08.9566667+00:00
Hi @Ali Asfar,

Thank you for confirming the test results.

Since the issue occurs:

with single meetings

recurring meetings

meetings without attendees

Outlook desktop

Outlook Web

and Teams desktop/web

while standard calendar events continue to save successfully, this now strongly indicates that the failure is specifically related to the Teams online meeting generation service associated with the affected account, rather than the calendar itself or any local client issue.

At this stage, the remaining troubleshooting would mainly need to be performed from the Microsoft 365 administration side, particularly around Teams and Exchange Online account provisioning.

Please ask your Microsoft 365 administrator to check the following:

1/ Temporarily remove and reassign the Microsoft Teams license for the affected user.

2/ Verify that the user is correctly enabled for Teams meetings and is not affected by a custom Teams meeting policy issue.

3/ Check whether the issue persists after forcing a Teams policy refresh and mailbox reprovisioning.

Because the issue reproduces consistently across all clients and only when generating a Teams meeting link, this may ultimately require the administrator to open a Microsoft 365 support ticket for backend Teams/Exchange integration investigation if the reprovisioning steps do not resolve the problem.
Ana Le 2,345 Reputation points Independent Advisor

2026-05-25T11:31:47.13+00:00

Hi @Ali Asfar, just checking in, how is the issue going on your side? If you still need help or run into any problems with the steps, feel free to let me know.

Answer 3

SIL GROUWSTRA 0

We have this same issue. Office365 / Windows. When i do a meeting without attendees, it works normal (no "Something went wrong" message) and the calendar item appears as usual.

Hornblower409 14,600 Reputation points

2026-06-23T12:17:23.2966667+00:00

@SIL GROUWSTRA said

When i do a meeting without attendees, it works normal (no "Something went wrong" message)

You will probably not get any help for your issue by commenting on an older post. I would suggest that you start a new thread using the "Ask a question" button at the top of this page to create a new Question and include the details for your specific problem. (You can put the link for this page in your new Question for reference)

Recurring "Something went wrong" Calendar Event Creation Error

Update the "Request" section to this:

3 answers

Update the "Request" section to this:

Your answer