If your computer is connected to a school or corporate network, it is possible that a direct internet connection from Teach2000 is forbidden. In that case a proxy server is required.
You can configure a proxy server in the settings window.
Open this window by selecting [Settings][Preferences] in the menu. Open the advanced settings.
Check 'Proxy settings'.
Enter the server address. You can ask the systems administrator for details.
If a login is necessary, enter the network account details.