The default server behaviour is to interact with a user to download and install Skype for Business Web App to join the meeting.
Create meeting skype for business web app. Follow your browsers instructions for installing the Skype for Business Web App Plug-in which is required for audio video and screen sharing. In the Skype for Business Web App meeting window press the F9 key. Select Join the meeting then wait for the plugin to create a popup window.
Depending on your version you may see Join Online Meeting Follow your browsers instructions for installing Skype Meetings. Follow your browsers instructions for installing the Skype for Business Web App plug-in which is required for audio video. To join a meeting by using Skype Meetings App or Skype for Business Web App just select Join Skype Meeting in the email or calendar meeting request you received.
Starting with CU5 Skype Meetings App is available as a replacement for Skype for Business Web App. Open the meeting request in your email or calendar and select Try Skype Web App. Press Enter to join the meeting with Skype for Business Web App.
Skype Meetings App offers a simplified browser experience for downloading and installing the app and joining meetings including one-click join for. Open the meeting request in your email or calendar and select Join Skype Meeting. Collect logging information for the current Skype for Business Web App session.
If you are still having trouble your system maybe blocked from installing plugins and you may need elevated rights to do so. In the Skype for Business Web App meeting window go to More options Meeting Options General. See this stackoverflow answer for more about how to do this.
Open the meeting request in your email or calendar and select Try Skype Web App directly below the link to Join Skype Meeting If prompted to install a plug-in or allow an application to run follow the instructions below this section. Skype for Business Web App is an Internet Information Services IIS web client that is installed on the server running Skype for Business Server and by default it is deployed on demand to meeting users who do not already have the Skype for Business. Enter meeting details in the Message box and set the start and end date and time.