Hi @Alison,
Welcome to Microsoft Q&A forum.
Thank you for reaching out regarding the issue that the “My Templates” add‑in is missing in Outlook classic has been reported by multiple organizations recently. We sincerely apologize for the inconvenience this issue has caused.
Based on my research, Microsoft has confirmed an ongoing service incident affecting Outlook/Exchange Online (Incident ID: EX1183224). A portion of their infrastructure responsible for mailbox connectivity is underperforming. As a result, some users may experience issues with accessing the My Templates and Viva Insights Outlook add-ins in Exchange Online.
For your reference: Service health - Microsoft 365 admin center
Note: Access is limited to Microsoft 365 Global Administrator. Please contact your IT admin if you don’t have access.
The next update is expected on November 22, 2025. Service availability is steadily improving toward normal levels, in the meantime, I’d suggest using Signatures as a temporary workaround, it’s not exactly the same, but it can help. Just a heads-up: as a forum moderator, my testing environment is limited, and I cannot access to Microsoft’s internal databases to dig into the root cause of this issue.
At this stage, no action is required on your part. Once systems are fully restored, Outlook should begin functioning normally again without the need to make changes to your settings or devices. That said, I kindly hope you can remain patient a little longer while the engineering teams continue working hard to fully restore the best possible experience for all users.
Also, since many others in the community may still be unaware of this incident, if you found this information helpful, please mark the answer as “Accept answer”. This will help surface the post to the top so others facing similar issues can easily find it.
Thank you again for being part of the Microsoft Q&A community. If you have any further questions or updates, feel free to reply here. I’ll be happy to assist further.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
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