Briefly, ports are like "channels" on a TV where each channel carries different "programming". Channel 25 (aka Port 25) is typically used to send e-mail traffic. Channel 110 (aka Port 110) is used to retrieve e-mail from a mail server using the POP3 protocol. Some larger ISP's typically block Port 25 to help them fight spam, denial of service attacks, and hacker attacks.
If your ISP is blocking port 25, you can "change the channel" and use port 366 as an alternate. You can normally change the port used in your mail client mail account settings. Please refer to your e-mail software help files for specific instructions on how to change your SMTP port number.
Also remember to allow that port through your personal firewall, if you're using one. Keep in mind, too, that some ISP's may not allow you to send mail through ANY port unless you use THEIR SMTP servers to send mail. Therefore, you may not be able to use our mail server for outgoing mail at all. You will need to contact your ISP to find out what their policy is.
To change your port settings in Outlook XP, 2002, and 2003 use the following steps:
1. Click the Tools > E-Mail Accounts menu in Outlook
2. Click view or change existing e-mail accounts
3. Select the e-mail account you want to change from the list and click Change
4. Click the More Settings button on the next window
5. Select the advanced tab and change the outgoing server port number to 366 and click OK, then Next, and Finish.