Bookings not loading through Microsoft Teams (desktop)

Hi @LD,

Welcome to the Microsoft Q&A forum.

Thank you for sharing the information.

I tried reproducing the issue in my test environment and encountered a similar problem. When opening the Booking app integrated in Teams, the system displays the same error code as the one you shared.

In this case, I recommend reporting the issue to Microsoft Technical Support so it can be further investigated and verified. Please follow the steps below to create a support request:

Note: To create a support ticket, your account must have Global Administrator permissions. If you do not have this role, please contact your organization’s IT department for assistance with the steps below.

Steps to create a support ticket:

1. Go to admin.microsoft.com
2. Select Help & Support
3. Enter the title: Need support to investigate the Bookings app
4. Click Contact Support
5. Choose your preferred contact method

While waiting for Microsoft Support to investigate the issue, you can temporarily continue working with Bookings via the integrated Outlook app or by accessing Bookings on the web.

I hope this information is helpful

If you have any questions or need further assistance, please feel free to share them in the comments on this post so I can continue to support you.

I look forward to continuing the conversation.

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Based on the error and the fact that Bookings previously worked in Teams, this is most likely a transient or service-side issue with the Bookings app rather than something specific to the local Teams client.

To narrow it down and work around it:

1. Confirm prerequisites
   • Ensure the account still meets the Bookings-in-Teams requirements:
     • Mailbox is in Exchange Online.
     • Microsoft Bookings is turned on for the organization.
     • The account has a license that includes Microsoft Bookings and supports Teams meeting scheduling (for example, Microsoft 365 Business Standard, E3, E5, etc.).
   • If any of these changed recently (license removal, mailbox move, or Bookings disabled), Bookings will fail to load in Teams.
2. Try Bookings outside Teams
   • Open Bookings directly (for example, via the web or Outlook hosted app). If it also fails there, it indicates a broader Bookings/service or licensing problem rather than a Teams desktop issue.
3. Use an alternative client as a workaround
   • If the issue is only in the Teams desktop client, use Bookings via Teams web or the standalone Bookings experience while the problem is investigated.
4. Admin checks
   • A Teams or Microsoft 365 admin can:
     • Verify Bookings is enabled for the organization and for the user in the Microsoft 365 admin center.
     • Check any Bookings app policies or Teams app setup policies that might have been changed and could be blocking or altering Bookings behavior.
5. If the problem persists
   • If prerequisites and policies are correct and Bookings still will not load in Teams, this may be an active service issue. An admin should check the Microsoft 365 Service Health dashboard and, if needed, open a support ticket with Microsoft, referencing that Bookings fails to load in the Teams client while prerequisites are satisfied.

References:

• Manage the Bookings app in Microsoft Teams