Hi @A Ska
Based on our research, if you enable MFA for all users in your tenant, you may end up blocking Teams rooms devices from signing in to Teams and other Microsoft 365 services. To avoid this, there are a few possible solutions that you can try:
- As @Carlos Solís Salazar mentioned, you can manually enable MFA for each user account in the Admin Center and skip the Teams rooms devices. For more details, you may refer to the article.
- Alternatively, according to the article, you can use security defaults to enable MFA for all users, but you need to exclude Teams rooms devices from the security defaults. You can do this by creating a group that contains all the Teams rooms devices and adding it to the exclusion list in the security defaults settings.
Hope the above information is helpful for you!
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