As with previous versions of Communications Server, there are two major gremlins with the Front End role: certificates and DNS. The new Deployment Wizard takes most of the guesswork out of certificate generation by automatically filling the SAN fields with the appropriate FQDNs for a given deployment. However, in more complex environments manual configuration might be necessary.
The added convenience of the Deployment Wizard doesn't lessen the importance of certificates. They are still core to all server and server-client communications. DNS, on the other hand, is not automated. For each pool created, the administrator needs to create an A record for each pool pointing to the load-balanced VIP for multiple-server pools or to the front end IP address for single-server pools.
The Lync Server event log is also a good place to check for errors. From the Start menu, select Administrative Tools, and then select Event Viewer. Expand the Applications and Services Logs item and select Lync Server. All events related to Lync Server functions reside here. Often, the error description is enough to identify the problem and make clear the resolution.