User Configuration > Administrative Templates > Skype for Business 2016 > Microsoft Lync Feature Policies
User
HKCU\software\policies\microsoft\office\16.0\lync
Uploads the sign-in failure logs to the Microsoft Lync Server automatically for analysis. No logs will be automatically uploaded if sign-in is successful. If this policy is not configured, then the following happens: For Lync Online Users: Sign-in failure logs are automatically uploaded. For Lync On-Premise Users: A confirmation seeking consent from the user is shown before upload. When this is disabled, sign-in logs would be uploaded to the Microsoft Lync Server for both Lync On-Premise and Online users automatically. When this is enabled, sign-in logs will never be uploaded automatically.