Drop outs/disconnections are usually due to network issues - if the client loses connectivity with the server the connection will drop and they will need to reconnect. Users experiencing these issues are recommended to:
1) Connect to their Internet provider with Ethernet if using a wireless connection. Wireless connections, especially if shared, can easily become congested or suffer signal interruptions.
2) Simply their open application landscape. Close any unnecessary applications especially those that consume bandwidth - VPN, Email, Other Web browsers, etc. To have a flawless experience one should do everything possible to dedicate their internet bandwidth to the webinar.
3) If you run into issues you can have participants check their bandwidth with: http://www.speedtest.net -- this will help them get a handle on the quality and upload/download speeds they are actually getting.
4) During a webinar there is a colored rectangle (usually green) in the upper right hand of the screen at the end of the Webinar controls. This is an indicator of network quality. To have a user check their current status you can have them mouse over it to see the current settings. If their network strength is poor (rectangle turns orange) see the recommendations above.
[Figure: Connection Quality Check.png]