Private channels without using exchange online

[Stefan Fried]

to be honest, i'm not sure if i should laugh or cry.

I would like to explain you a situation i have at the moment and i bet that i need to open a ticket at microsoft, but MAYBE some of you can explain me the real reason behind of the problem

I have users who do not have an exchange online account.

Whenever they get added to a private channel, the private channel is NOT visible in the Teams Client whereas in the Mobile client they SEE the private channel where they can write messages and interact with the others.

But that's not all:  these users can not even create any private channels although everyone is allowed from a policy point of view.

I have done a bit of a research and read that for the compliance part, all the messages within private channels are kept within the individual mail boxes of the private channel members.

Could this be the reason for this strange situation ? 

i'm wondering how this compliance works for GUEST users. I mean they do not necessarily have exchange online not either.

thank you

[#2]

Hi,
I don't think it is the reason you got problems. Messages are saved in Exchange mailboxes is for compliance reasons so that admins can search for messages with eDiscovery. Teams does not read from the Exchange mailbox, it only stores a copy of the messages there. It is the same for 1:1 private chat messages.

If you have Exchange On-Premises these messages will be stored in a shadow mailbox online, but the user object (not mailbox) have to be synced from on-premises Windows Active Directory but I guess you already done that.

For guest users the same method is used with shadow mailboxes, so a cloud-based mailbox that only stores chat history is created for guests.

Do you have the same problem if you test the web application of Teams? https://teams.microsoft.com

[#3]

thank you @Linus Cansby 

can you explain a bit more on that "shadow-mailbox" ?

Can i see them somehow ?

for a guest (who is not member of any o365 tenant), where is this "shadow mailbox" then ? 

regarding your question:

intersting, i do see the private channel in the web view as well  (so web and mobile view is fine...only the client does not show the private channel)

--> my teams client is on the latest available version  :)

thx

stefan

[#4]

Log out of your client and back in to clear cache, it might force it to pop up.

[#5]

Also, according to this article: https://techcommunity.microsoft.com/t5/Microsoft-Teams-Blog/Microsoft-Teams-supports-eDiscovery-for-...

It appears you have to contact Microsoft to have the Shadow mailboxes configured. Not sure about the guest accounts.