we are currently developping on 126.96.36.199. Everything works fine on all developer's lab computers and tester's lab computers, except all training lab computers. When opening a pick applet, a warning popup appears, displaying no message. Same thing happening when I click on Help->About view, but a second popup displays "AppErrCommunication". When I try with my developer computer connected to the same environnement, it works fine. Training computers are on Windows XP Pro with SP3, Internet Explorer 8.0 with SP3 and everything was ok before installing IE8 on 188.8.131.52. High interactivity active X (184.108.40.206 version) is not damaged. Siebel web application is in the trusted sites and enable every options (except one but it's suppose to be ok). Everything is enable in IE advanced options.
You possibly have your proxy settings to be set correctly on your training lab computers. If the browser encounters a problem and needs to close, proxy settings need to be altered. Move the message that says there is a problem and make a note of the server address (IP/URL) which is launching the Siebel application. Now you need to include the Siebel server as a proxy exception (IE Options, Connections, LAN settings, Advanced (proxy server settings), Do not use proxy server for addresses beginning with <noted address>).
Let me know if this helps.