This is a connection problem between your client and the VirtualLab server. There are a few things you can try:

1. Turn off 'Automatically detect Proxy Server settings' from the Login page of the Client:

Click 'Connection Settings'

Then uncheck the first option if it's checked. If it's NOT checked, then check it and try to connect.

You can also check your settings in Internet Explorer to make sure that they're correct:

If none of this allows you to connect, then you need to make sure that nothing is blocking your connection, like a Firewall (VirtualLab uses port 80). For support with this, please see your network admin.