4 ms·
If they're blocking SMTP, doesn't it make sense to block the encrypted ports too, e.g. 587? But if they're blocking 587, then how do people with these ISPs use
by bscphil 7y ago
If they're blocking SMTP, doesn't it make sense to block the encrypted ports too, e.g. 587? But if they're blocking 587, then how do people with these ISPs use their own email clients like Outlook (or whatever it's called these days) with third party email providers, e.g. Gmail?
- jlgaddis 7y ago25/TCP is, technically, for MTA <-> MTA traffic, so many (residential, in particular) ISPs block it because "you shouldn't be running servers". 587/TCP is the "submission" port and is exactly what people should be using instead of 25/TCP (it usually -- but not always -- requires authentication and is pretty much never blocked). Indeed, that's the intended purpose!