Solution: Can’t send email on O2 Broadband?
I’ve just had O2 Broadband installed at home, and the first thing I noticed is that port 25 (SMTP) is blocked to prevent spam and other malicious emails being sent through their network. This is fairly common place these days (although slightly pointless), and o2 force you to use their email server to send through -
Outgoing Mail Server (SMTP)
Host Name: smtp.o2.co.uk
User Name: youro2username@o2.co.uk
Password: youro2password
Outgoing Settings
Use SSL: Off
Authentication: Password
Server Port: 25
A solution
If like me you don’t want to use the o2 mail server (probably because you have your own setup or want to use your work email) you may be able to use authenticated SMTP. By providing a username and password, and using port 587 (the authenticated SMTP port) instead of port 25, you should be able to connect. You can change this setting in Outlook/Entourage where your account details live, or on your iPhone in the settings.
Alternative solutions
If your email provider doesn’t allow authenticated SMTP access on port 587, you can try…
- ask if they allow authenticated SMTP access on an alternate port.
- if you can’t get access to an alternate port, you could use a service like http://www.smtp2go.com
- and last but not least, http://www.mail2web.com provide free access to your email through your browser.
There’s some more information here if you need it.
JohnJones 2:21 am on October 31, 2008 Permalink | Log in to Reply
hi there
blocking port 25 is VERY valid especially if the ISP provides a relay !
If you are submitting mail to a server outside the network (in this case outside O2) then you SHOULD use PORT 587 its the mail submission port !
if your administrator does not understand you should only allow authenticated (preferably encrypted via TLS ) on 587 that way they know all traffic is from local users while port 25 is from users/servers delivering mail originating outside the organization
make sense ?
regards
John Jones
http://www.johnjones.me.uk
grimfandango 9:17 am on October 31, 2008 Permalink | Log in to Reply
Hi John
Thanks for your comment.
Agreed, mail via port 587 should be authenticated (it is on our mail server), but the comment I made about blocking mail on port 25 being pointless was more about the technical ability of spammers and virus creators and how blocking port 25 won’t make much difference to them. Lets face it, if they want to send an email, they’ll do it some other way
JohnJones 5:57 pm on November 2, 2008 Permalink | Log in to Reply
hey there
YAY you get it !
(you would be surprised how many people dont understand 587 and having more and more people submit mail on 587 is a great thing…)
regarding the pointless blocking of port 25 its actually cuts spam traffic on a network by about 37% which is HUGE and makes tracking of infected machines much much easier !(simply look in logs and you can automate shutdown/suspension of account etc )
scary but true
regards
John Jones
http://www.johnjones.me.uk
smtp2525 5:13 pm on September 7, 2009 Permalink | Log in to Reply
If you’re interested, Unified eMail provides SMTP relay services for personal and business use over alternate port 2525. Check out: [link removed]
grimfandango 5:45 pm on September 7, 2009 Permalink
link removed because you don’t offer a free personal account, and therefore it’s blatant comment spam.