Forum Discussion

Iron Contributor

Jan 28, 2021

Solved

"We can't setup the conversation because your organizations are not setup to talk to each other"

I get this message when I try to Teams chat with another tenant. Do both tenants have to be in "Teams Only" mode at the org level for this to work? Tenant A is in Islands Mode with external access ...

microsoft teams

Joe McGowan
Feb 09, 2021
ChristianBergstrom

Looks like I found the issue. When I did a Get-CsTenantFederationConfiguration, the AllowedDomains setting was blank. I added "AllowAllKnownDomains" and chat is working now.

https://www.thirdtier.net/2020/04/10/microsoft-teams-does-not-allow-remote-users-to-connect/

I think this setting was inherited from our Skype for Business configuration which had federation disabled, but that is a guess. Our tenant is still in Islands mode, target is Teams only, and I'm able to chat with them now.

Abdullah_Ollivierre

Copper Contributor

Apr 13, 2023

Joe McGowan

The PowerShell cmdlets mentioned here were certainly helpful (using the Microsoft Teams PowerShell module --not the Skype for Business PowerShell module--)

I fixed this by adding the domain to the allowed list of domains in the Teams Admin center then waited for 10-15 minutes. I was now able to collaborate with users outside our tenant.