Recently in conversation with fellow MVP Steven Collier, we had differing views on how chats can be initiated by guests based on our experiences. As it wasn’t clearly documented I sought clarification from the Teams team.
When a guest joins a team, they become a member of the Azure Active Directory and gain visibility of the directory to a certain extent.
How this plays out is that a guest can initiate a chat with any another person in the tenant, in a couple of different scenarios:
Name-based discovery only works for people who exist in the same teams as you
What this means is that if I am in a team with John Doe, I can start a chat with John simply by typing his name.
Similarly if another guest called Jane Smith (Guest) is in the team with me, I can also initiate a chat with Jane by typing her name.
However, if Damien Margaritis is not in a team with me – I cannot initiate a chat with him by typing his name:
Which leads us to….
Chatting with people outside of your teams
Similar to how federation works in Skype for Business; you can initiate a chat with someone in the tenant if you know their email address.
So in the previous example where I was not able to find Damien Margaritis by name, I can however find him by his email address of email@example.com.
And now you know!