@lakshmi Thanks for reaching out to us. Yes, it is possible to use a Teams bot with external users via Microsoft Teams' guest access or external access features.
- Guest Access: Guest access in Teams allows you to add an individual user (regardless of domain) to a team, where they can chat, call, meet, and collaborate on organization-wide shared files using Office cloud services. Once added to a team, guests can interact with the bot in that team.
- External Access (Federation): External access lets your Teams users communicate with users who are outside of your organization. By using external access, you can use Teams to collaborate with people in other organizations or, if necessary, with people who are still using Skype for Business. However, please note that these features are designed for collaboration with individual users and might not be suitable for providing broad access to a bot for many users across different organizations. For external users who do not have Teams or a Teams license, you might want to consider other channels for your bot that are more accessible, such as a web chat interface embedded on a public website. Microsoft Bot Framework, which is commonly used to create bots for Teams, also supports deploying bots to a variety of other channels like Web Chat, Facebook Messenger, and more.
Reference document -
https://learn.microsoft.com/en-us/microsoftteams/guest-access
https://learn.microsoft.com/en-us/microsoftteams/communicate-with-users-from-other-organizations
Please take a look and let us know if you need more help, also, Teams development experts may provide more details.
I hope this helps!
Regards,
Yutong
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