One Way Federation – Lync

One of our client has been using a Lync 2010 OneBox from AudioCodes for some years without issues. Last week they migrated from Exchange On-prem to Exchange Online and they started having an issue with Federation.

Federation was working two ways with any Skype For Business or Lync on-premise environment without any issues. The federation with Office 365 was only one way:

• Users from the client company could initiate IM with federated partners and see their presence.
• Other Skype For Business Online users could not see the presence of the company users or start IM’s.

Nothing was changed on the Lync on-premise environment but I still ran all the normal checks, DNS, Certificates, HostedProviders, … all was looking good.

I then used Snooper to see what was happening, and got the following error:

• ms-diagnostics: 13012;reason=”No Routable Endpoints.”;source=”AM41E02FES05.INFRA.LYNC.COM”;Callee=”user@domain.com”;appName=”InboundRouting”

Additionally I saw some strange entries on the “recorded routes”.

• They were all pointing to Office 365 with no mention of the Lync Edge server.

Further investigation showed that when they have been migrated to Office 365, the administrator activated all the users with E3 licenses (the full package).
One of the components of that E3 license is the “Skype For Business Online Plan 2”. However in this scenario there is no Hybrid Lync/S4B connection with Office 365 and the One Box has it’s own domain.

Once we disabled the “Skype For Business Online Plan 2” from the E3 licenses for all of the users, everything went back to normal and two-way federation was restored.