A mass of dedicated Mac users are spending this week holed up in the hotels and hostelries surrounding San Francisco’s Moscone Center. During that time, more than one of them will attempt to send an email message to his or her loved one, only to be thwarted by the dreaded “Relaying Not Allowed” error.
This occurs when you try to send messages through your regular email account via the Internet connection in your hotel or at the local hotspot. Asking one ISP to send your email via the SMTP service of another ISP (relaying) is often forbidden by the first ISP (the hotel, in this case) in order to discourage spammers from shuttling their effluvia around the web.
Fortunately, this problem can often be rectified by simply reconfiguring the SMTP port settings in your email client.
Just launch that self-same client, go to your account settings (in Mail you’ll find it in the Accounts tab of Mail’s Preferences, in Entourage you’ll find it by choosing Tools > Accounts), and scout around for a way to configure your outgoing mail settings. Within such an area, seek out a field that includes the port number for outgoing (SMTP) mail. This is likely to be 25—the outgoing port that’s commonly blocked to prevent relaying. Those who configure email servers often create alternate SMTP ports to get around this blocked port problem—ports 587 and 2525 are two alternative ports I’ve come across in my travels. Try changing the port setting to one of these numbers and cross your fingers.