Symptoms
A string is usedĀ if Microsoft Skype for Business 2015 (Lync 2013) encounters a generic error during a conversation. When Skype for Business 2015 (Lync 2013) tries to format the string, the client crashes.
Resolution
To fix this issue, install the December 6, 2016, update (KB3127976) for Skype for Business 2015 (Lync 2013). Note Lync 2013 was upgraded to Skype for Business in April 2015.