Troubleshooting Skype for Business integration
Last updated January 22, 2018 Skype for Business
There is an issue where non-Skype for Business participants will drop from a Skype for Business meeting after exactly 90 minutes. This is due to the Microsoft settings.
If you have on-premise Skype for Business, you can control these settings; for Skype for Business Online, you cannot.
Skype for Business Server has a setting which controls how long anonymous users are allowed in a meeting.
The setting is AnonymousUserGracePeriod and the default value is 90 minutes.
You can check the value with this shell command:
For more information, refer to Microsoft documentation.