Microsoft is changing the default setting for guest access to Teams from Off to On. This won’t affect tenants already using Teams, but it’s a good opportunity to review how guest access is used in tenants and consider whether existing guest accounts are needed or can be removed. This post offers some ideas about using policies to control guests and how to check what these accounts are used for.
https://office365itpros.com/2020/12/08/teams-default-guest-access-setting-changing/
