Some times our web applications or windows service or windows desktop applications throws "unable to connect to the remote server".

Make sure url or IP address is correct.

Your port might be in use by other process. solution:
Proxy server Make sure that your not using Proxy server to access internet. If you are using proxy server to access internet,
                   contact your administrator and get the network credentials, IP address and port. Add those details in you application
                   to let it use proxy server.

Anti virus:     if you are using ESET antivirus, you need to setup rules init to allow your application in / out request on xxxx port number.

                   symantech: Disable it and then try.

Application: Application is trying to access apache server url. URL maybe case sensitve use correct url. 

                  use command prompt and execute telnet command

Telnet   ip_address   port_number

and see the response.

e.g.

Open command prompt and type

Telnet 198.168.1.1 80




If you see a blank screen, that means you are able to connect and your internet is OK.
If you see connection timeout or unable to connect, there are many reasons.

1. The website you are trying to connect is down or.
   
2. The your network administrator has changed the password or proxy server address.
   Ask your administrator about changed new proxy address or port or password and
   configure your application accordingly.
3. You might have installed new antivirus where it founds your application as spyware.
   Configure your application.