Hi peeps. I’ve recently started receiving errors when sending emails to hotmail accounts, they are being bounced with the following error:

“SC-001 Mail rejected by Windows Live Hotmail”

It appears, at least in my tests, that Hotmail doesn’t like receiving emails from smtp servers that are different to the senders email address/domain. In other words if the senders domain is ge3k.co.uk but the email is received from relay.o2broadband.co.uk it will be flag as spam and bounced back.

For me it hasn’t been happening until recently, so I’ve now been forced to start using my domains smtp servers instead, but this brings up another issue. O2 actively blocks port 25 used for outgoing mail, and instead provides the above mail relay server address for people to use. They claim this is to prevent mail spammers using their broadband service to spam people, but this is a poor excuse at best.

This problem is more of an issue for O2 customers who don’t have a static I.P Address, this is because these customers are lumpt with using O2′s replay server only, whereas customers who have a static I.P Address can send using their own domains smtp server. Strange, yes, although I have had sending issues before, even though I do have a static I.P and I’m a business customers, hence the reason why I switch to using O2′s mail replay server in the first place.

I hope this helps to explain this issue a bit more for those having the same problem.