O2 Blocks Port 25
It has only been recently that I have got the my broadband service from O2 and I have already hit a wall. I tried sending email through the internationally recognised default port (25) and it would not let me do it. I thought it was my email provider was having problems but just to make sure I set up my SMTP using Google’s Gmail service and it did the same. I did some Googling and found that O2 blocks port 25 unless you have a static IP. This is just wrong!
O2 does provide a “relay” server but doesn’t this mean every single email you send using their server can be farmed, archived or used for other purposes?
Most email providers use port 587 as an alternative to port 25 and this solution has worked for me but it’s a matter of principal! The internet should be free (as in freedom not beer).
O2 forum post about port 25 being blocked
A more proactive solution to the issue
Most ISP block 25 now, mainly cos spam is so bad.
BT dont block 25 but you need domain trusting or mega spam filters.
As far as i no though O2 had a static IP with all there products, but looks like the stuck a premium on it now :/