Question: I'm running XP firewall. How do I find out what port number I'm using? 

Answer: IP ports are dependent on what application you are using.  Viewing web pages uses port 80. Downloading e-mails uses port 110 and sending e-mails uses port 25.  Gibson research www.grc.com has tools that can determine what ports you have open and can tell you if there is any security risk.
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