Skype for Business Phones shows “Connecting to Lync Server…” after default pool certificate change

Run into this issue (Skype for Business phones showing “Connecting to Lync Server…”) with Microsoft certified phones and devices connected to Skype for Business Server 2015 environment after replacing the Default certificate of the pool. In this specific case, there are two Certificate Authority (CA) in the environment – an old Root CA, a single…