I'm seeing the same behavior with the latest version of Office 2016's Skype for Business client....Using 10166, SP3 and Office 2016 365 Pro Plus....can anyone confirm if you get the crash with Skype for Business....open an IM window and minimize the IM and the Skype for Business main window....it automatically crashes the program. Wondering if someone else can confirm...Windows 10? Office 2016? Or is it Exchange policy trying to switch the program back to Lync 2013? Googled it...nothing very relevant.