Error when switching the Teams bot

Hi @Burgos Shirnava

Thank you for posting your question in the Microsoft Q&A forum. 

I understand how confusing it can be to see a 401 error right after changing from MultiTenant to SingleTenant, and I apologize for the inconvenience this has caused. 

From what I’ve found, this issue has come up quite often, especially for developers switching from MultiTenant to SingleTenant. It seems to be a known issue in the Bot Framework SDK and backend services, which can result in authorization failures for SingleTenant bots. 

You may find these references helpful: 

Single-tenant bots don't work in new Teams client · Issue #11153 

SingleTenant MS Teams Bot returns 401 - "Authorization has been denied for this request"

In the meantime, the most effective approach is to create a new bot app configured as SingleTenant from the start. If creating a new bot isn’t an option, you may need to wait and monitor Microsoft announcements and Bot Framework SDK updates, as improved SingleTenant support is expected in future releases. 

I hope this helps. If you need any further assistance, please feel free to let me know. 

If the answer is partially helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".     

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.