We are in a process of migrating from lync 2010 to 2013. I have a problem with Lync 2010 mobile client that i can't understand. When a user is on 2010 pool ... the mobile client works from outside using 2013 edge. When i move the user to 2013 pool the client can't connect to the server.? Why is that? The 2013 client doesn't work at all since is not published with the TMG. All dns records still points to the 2010 pool .. that is federated with the 2013 pool.