Forum Discussion
Private channels without using exchange online
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