Many users may have a firewall without even knowing that it is there, and if you have experienced these symptoms then the chances are that a firewall is causing it. There are many different firewalls in common use, and they fall into two categories: hardware and software.
A hardware firewall is a physical device, and is much the better of the two kinds, offering greater security. Typically you may have one of these inside a cable modem if you have cable internet, or in your network router if you are using a computer on a local home or company network. A software firewall is a program which runs on your computer. There are many different software firewalls in common use. Proprietry brands include Norton, FireFox and McAfee - one of these often comes pre-installed on a new PC nowadays. All Windows XP users will have Windows Firewall, which comes as part of the operating system, and may quite likely have one of the well known proprietry firewalls pre-installed as well. If you are running Windows XP with Windows Firewall, here is how to unblock port 113 in 10 easy steps:-
1) Go to Windows Start menu and click Control Panel (you might have to choose "Settings" and then Control Panel).
2) In the control Panel, look for the Windows Firewall icon, and double click on it to open Windows Firewall.
3) Make sure that the "Don't allow exceptions" checkbox is NOT ckecked (uncheck it by clicking on it if you see that it is checked).
4) At the top there are 3 tabs labelled General, Exceptions and Advanced. Click the Exceptions tab.
5) About 3/4 of the way down you will see a button labelled "Add Port" - click this button. A box will pop up with two places where you have to enter some text.
6) In the "Name" box type "Identd" (in fact you can call it anything you like, but Identd is the correct name).
7) In the "Port Number" box, type 113.
8) Click OK in the pop-up box. You should now see "Identd" listed in the exceptions in the main Windows Firewall window, with a tick in the checkbox next to it.
9) Click OK in the main Windows Firewall window, which will close this window.
10) Close the Control Panel. Windows Firewall should now allow you to connect to the playing room without any further adjustments.
Remember if you have any other firewalls in operation you will need to unblock port 113 for TCP in these as well. Hardware firewalls usually come with documentation which should be consulted. If you are on a local network with its own router, you may need to consult the network technician and ask to have port 113 unblocked in the router. Software firewalls can usually be set to allow access to any specified port, with steps similar to those outlined above for Windows Firewall, although the precise details will vary. If you suspect you may have another software firewall on your computer but are unsure, go to Windows Start Menu, click "Search", select "All files and Folders", then search for files with names including "firewall", then repeat for names including "norton", "firefox" and "mcafee". If you find any programs that look like they may be firewalls, double click on them to open the suspected firewall, and look for a place to change its settings.