Some providers block access to a part of ports. Especially often they use this reception at connection on cheap unlimited rates. If any given website is not loaded, or any given program refuses to connect to the server, it is useful to check what port at the same time is used.
Instruction
1. If your computer is connected to the Internet changeably, carry out its connection to a wide area network, for example, having turned on the modem and having started the program servicing it. Also in advance start the browser or the program which you wish to connect to the server on port unknown to you. Try to enter the website address into an address bar of the browser: if after that the colon and the port number automatically is added to it, further actions can be not carried out - it will become known to you and so.
2. Open the console. In the Linux operating system for this purpose start the rxvt, xterm or Konsole program. In Windows use the cmd program ("Start-up" - "Execute" - to enter cmd - "Ok").
3. When the console opens, start process of connection of the program interesting you to the Internet or begin update in the browser of the page interesting you then immediately (so far connection was not closed) enter the netstat command into the console - ano (before minus the space is, and after it - no).
4. Two tables will be displayed. Pay attention to the column "Foreign address" (or Foreign Address) the first of these tables. In it the IP addresses will be listed, after each of which through a colon the port will be specified. Usually it has number 80 which is open at all providers. If you see other ports, call support desk of provider, call the rate and ask whether such ports are open for you. It is also possible to set the corresponding password in a forum of support of provider. If it turns out that ports are closed, whenever possible recustomize the program so that it was connected to the server on other port. It is possible to browse page contents, using service Opera Turbo, Skweezer or similar. As a last resort, pass to more expensive rate, previously having learned whether then the port necessary to you will be open. Consider that opening of some ports creates security risk of a system.