Internet connection refused by the proxy server

Internet connection refused by the proxy server

The proxy server is refusing connections
Firefox is configured to use a proxy server that is refusing connections.
* Check the proxy settings to make sure that they are correct.
* Contact your network administrator to make sure the proxy server is working.
I am in the middle of my browsing activity when I encountered this error. The proxy server is refusing connections. I am connected to CCPROXY Server which is installed on the other computer that is directly connected to the internet. I have checked my proxy server and I think there is no problem on it, because some other computers are still connecting. There is no user restriction in the server. My network status says, "No Internet Connection".
Please help!
