port 25 blocked.. what are my options

[RabbieBurns]

The place Im at just now, the ISP blocks port 25 Outgoing(!) which makes using my smtp mail accounts impossible. I can connect to my vpn back home and send mail that way, but it slows down the browsing and downloads obviously..

 

Options I can think of are to run a smtp server on a different port on one of my servers back home..

 

Or a socks5 or something maybe and just setting it to go through that to send - would that work?

[Potato-Peeler]

Could you not contact the ISP in an attempt to get the port unblocked?

Failing that the South Africans recently tested carrier pigeons vs E-mail...

[kmount]

Chances are if they're blocking it you will be able to use their provided one on port25.

 

Or yes, you could enable smtp on an alternate port.

[RabbieBurns]

im just renting a room in the place only got the wireless password dont have any info or the account or account login details to use the isp smtp (unless it might work with no auth? worth a try...)

[RabbieBurns]

ah sweet. that works without authentication. thanks

[Michael]

Hmm why would any ISP want to block port 25? Seems a strange decision to me.

[RabbieBurns]

Hmm why would any ISP want to block port 25? Seems a strange decision to me.

 

I could see why them blocking it incomoing to stop you running your own mail server etc.. but yeh, outgoing is daft.

 

But using their one works. I should have tried it before tbh, I just assumed it would require login details.

[Fuzzz]

Hmm why would any ISP want to block port 25? Seems a strange decision to me.

 

It stops malware from sending spam.

[Michael]

But you can just change the port your application uses from 25 to something else. It's like ISPs trying to prevent users using bittorrent... you can change it to any random port. You don't actually gain anything blocking port 25 is what I'm trying to say

[Fuzzz]

It's the port 25 on the receiving side. If I want to send e-mail to, for example, hotmail.com, I have to send it to their mailserver on port 25.

 

Many ISP's block port 25 so malware can't send spam. If you want to send e-mail via SMTP you have to do that via their mailserver.

[kmount]

But you can just change the port your application uses from 25 to something else. It's like ISPs trying to prevent users using bittorrent... you can change it to any random port. You don't actually gain anything blocking port 25 is what I'm trying to say

 

If I'm an ISP and I ONLY allow outbound SMTP access to my SMTP server I can control exactly what's going out so anybody infected with mailers etc will show up quickly.

 

Most malware uses a 'known' smtp server either a listed open relay, or the one configured on the users outbound mail client so it can't be tracked back to John Smith running his own spam mail server on port 12345.

 

I've yet to see an RBC allow direct outbound SMTP access to anywhere other than their own boxes for this reason.

[powdarrmonkey]

Unless you're doing something funky like SPF, I'd always try and use the local ISP's SMTP server - it's closer to you in networking terms as well as geographical.

 

Failing that the South Africans recently tested carrier pigeons vs E-mail...

 

No, they didn't.

[powdarrmonkey]

But using their one works. I should have tried it before tbh, I just assumed it would require login details.

 

Only if you're outside their network. If you're inside, they already know where you live

[Michael]

I suppose it does protect the ISP if they can control what goes out, but still there are clearly ways around this as spam is getting an increasingly bigger problem every year.

[SC-UK]

The best port to try is 586 if anybody has this problem in the future and needs to authenticate.

 

My ISP blocks all SMTP traffic apart from to it's own mail servers on port 25. Change it to 586 (another common SMTP port), and it works without a problem.

 

Tom

[RabbieBurns]

I use the smtp of the provider i host my domains with.. but Ive just read their FAQ and found this:

 

Do you have an SMTP/Relay server?

 

Yes, we supply an authenticated SMTP relay service using the same username and password that your pop account uses.

 

We deliver the service on port 25 and port 2525 to allow for ISP's which block port 25 traffic.

[Cools]

I use the smtp of the provider i host my domains with.. but Ive just read their FAQ and found this:

 

see RTF FAQ lol all ISP's have another port to email to 568 (most common) and you 2525

[powdarrmonkey]

all ISP's have another port to email to 568 (most common) and you 2525

 

No, 'many' ISPs have an alternative port. Not all.

[Michael]

On the topic of spam/ports etc... what's always baffled me is why someone hasn't come up with a solution to truly fight e-mail spam. As far as I know SSL certificates cannot easily be changed or copied and these work great for banking websites for example. Essentially an SSL type certificate for e-mail, again sent encrypted.

 

It would theoretically be difficult for spammers to copy this, despite the fact they could successfully send an e-mail spoof. It would be near impossible to spoof an SSL certificate associated with an e-mail account and/or web domain.

 

You may be thinking that you can setup a private key and a public key but this typically between specific users who may e-mail regularly. There isn't a global SSL type e-mail solution which works well for secure websites today.

[Potato-Peeler]

 

 

 

No, they didn't.

 

Pigeon post faster than South Africa's Telkom | Mail Online

[powdarrmonkey]

SPF, DomainKeys and so on are already in place to do this, but it's such a huuuuge change to co-ordinate it's still in the planning stages. Some ISPs are adopting it gradually, but even of those most are cautious about rejecting mail (as oppose to tagging it) because of how little mail can be classified in the first place.

 

Chicken and egg problem, really.

[powdarrmonkey]

Pigeon post faster than South Africa's Telkom | Mail Online

 

I don't see any mention of SMTP (or, as this is the Mail, 'e-mail') in that article.

[Cools]

No, 'many' ISPs have an alternative port. Not all.

 

if ya say so.. you keep believing that

[RabbieBurns]

Cools how can you difinitively say anything with regards to EVERY isp in the whole world ?

[Michael]

Chicken and egg problem, really.

 

Absolutely you're right. And the chicken and the egg argument is an argument no one can win really; which I suppose is the state of play with regards to spam. I think you can reduce it but never remove it completely.