Ok, time for some tech speak! Many ISPs are blocking the outbound SMTP port 25. It allows ISPs to block spam sent out through their networks, but it tends to “punish” those who innocently need to send stuff through e-mail servers, rather than those belonging to their ISP.
The port 25 is chosen by default
In a nutshell, here are some of the possible scenarios that you might encounter when using port 25:
1. Sending an email from your Outlook Express or Outlook (assuming you’ve configured the email client to use the default port 25 for your SMTP server)
2. Submitting a web form (assuming the back-end was done using a SMTP method)
3. Using Groupmail to deliver email newsletter (assuming the Groupmail is configured to use port 25)
In short, your emails will be blocked and the worst thing is, they’re usually dropped without any returned error messages or notices to the sender. To overcome this issue, we’ve setup an alternate port. You can use port 8025 or port 587 instead of port 25.
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4 Responses to “Working Around Your ISP Blocking Port 25”
LK said:
May 5th, 2010
Dear Pin, been having problems again with streamyx. My company email is moon.com Have been able to send emails using outlook to other emails like gmail.com, hotmail.com but if i copy the email to my other colleagues or myself, at moon.com it does not come in. But this same email is received at gmail.com, hotmail.com Any suggestions? I tried your methods but cannot work
Two things, check what is the SMTP server you have configured inside your Outlook? And do you check the Spam folder in moon.com’s webmail and the Outlook?
Pin
Dennis said:
August 10th, 2010
Thanks lot. Was pretty frus with problem sending email from Outlook client in Starbucks, Celcom B/Band. With this suggestions, it works!… at least with my Celcom B/Band. Will try Starbucks later.
