Re: [exim] Urgent help needed. Exim 4.67 stopped working.

Dave Lugo wrote:
> On Thu, 17 Jan 2008, Daevid Vincent wrote:
>> After calling Comcast, it appears that yes, I have been port 25 blocked.
>>
>
> Is this consumer-grade, dynamic IP'd service? If so, it's not suprising
> that they blocked port 25. Given the amount of compromised systems on
> broadband consumer networks, blocking outbound port 25 is considered 'best
> practice'. If more providers did it, there would be a lot less spam.
>

I am not sure. Blacklists can list broadband customers IPs. While they will not
list ISP outgoing mail relays. Now some virus and trojans have evolved due to
port 25 blocking and are using ISP mail relays. And these are quite annoying to
filter out.
So in the absolute, there would clearly be less wasted bandwidth on port 25, but
I am not sure there would be less spam arriving in inboxes of mail servers
operated by spamaware mail admins.