Lync 2013 call forwarding - Issues with Call Forwarding

Are you in the middle of deploying a new SIP trunk deployment and having troubles with Lync 2013 call forwarding. The common problem is not allowing you to forward any calls to your cellphone, use call forwarding or simring. The first item you want to check is that EnableSipRefer is set to $False cmdlet: CsTrunkConfiguration -EnableReferSupport $False.