Turn on error logs in Skype for Business
support.microsoft.com › en-us › officeLocate and gather information from the Skype for Business log file. In File Explorer, navigate to the Tracing folder in your user profile directory—for example, C:\Users\<your alias>\AppData\Local\Microsoft\Office\<16.0 or 15.0>\<Skype for Business or Lync>\Tracing. (If you’ve just enabled Skype for Business logging, you’ll need to sign out of Skype for Business and then sign back in for the log files to be created.)