Error 404 when Lync phones sign in to Lync Server 2013 front-end servers during SBS failure recovery

Applies to: Lync Server 2013


Consider the following scenario:
  • You deploy four front-end servers and a survivable branch server (Windows SBS) in a Microsoft Lync Server 2013 enterprise standard pool.
  • You register multiple Lync phones to the SBS.
  • Many users sign in to all available Lync phones.
  • The SBS is then shut down.
In this scenario, the Lync Phone Edition devices may be unable to sign in to the front-end servers automatically. Additionally, the users may receive a 404 error code.


To resolve this issue, install the following update:
2937305 August 2014 Cumulative Update 5.0.8308.738 for Lync Server 2013, core components