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Old 08-04-2005, 08:35 PM   #1
ultrax
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my isp blocks SMTP port


I'm trying to set up sendmail to be able to send and receive email from the outside world. However, I can send emails to people from the outside but when I want to retrieve emails or ppl from the outside try to send me emails, it doesn't work. I'm assuming my ISP is blocking port 25.

Assuming to resolve that issue, you need to get somewhere a box from outside ISP to recognise the port 25. So it will be able to communicate with the ISP port then this box will forward to your own mail server port.

Is there any other alternative?
Are there any cheap services that you guys might know?? What u guys recommend?

I heard no-ip.com offers that service (mail reflector)
 
Old 08-05-2005, 12:54 PM   #2
comprookie2000
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I use DSL and I can go to my modems configure page (mine is 192.168.1.254) and open up ports that I want.
 
Old 08-05-2005, 01:40 PM   #3
ultrax
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You could change whatever port you might want in local.
But the question is: How to make it recognize by other mail server from outside world to know the port u have changed??

Let's say:

Someone from outside @yahoo.com want to send email to you using name@your_domain_name.
Technically, Yahoo smtp mail server port 25 will get in touch with your smtp mail server and by default it only knows port 25 which your ISP blocks to prevent some spamming reasons... And if it won't find that port, it will bounce back with an error msg.


Quote:
Originally posted by comprookie2000
I use DSL and I can go to my modems configure page (mine is 192.168.1.254) and open up ports that I want.
 
Old 08-05-2005, 01:44 PM   #4
comprookie2000
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You may be blocking port 25 in your modem, if you use one.
 
Old 08-05-2005, 01:47 PM   #5
ultrax
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Nope I don't block my port 25 but I know that my isp is blocking it

Quote:
Originally posted by comprookie2000
You may be blocking port 25 in your modem, if you use one.
 
Old 08-05-2005, 02:00 PM   #6
Matir
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If your ISP is blocking port 25, then your SMTP server will be unable to receive any email. Just use a server elsewhere. If they're blocking port 25, then most likely, running a server is a violation of the TOS.
 
Old 08-05-2005, 02:02 PM   #7
Half_Elf
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most ISP are blocking port 25, at least, all canadian ones do this.
Out of the "external mail forwarder" or the " mail reflector" I doubt there is any others way to bypass this. If you want to install a SMTP server for learning purpose or for personnal use, you could install a local mail server and "rewrite" new "FROM:" header to your outgoing mail before sending this to your ISP mail server (which may be open to their inside network... at least my ISP is like this). Making the FROM statement to be your ISP real mail would allow you to send mail from your local server and some tweak may allow you to download your mail from their pop to your local server. But this would only be useful if you plan to teach yourself the art of SMTP serving I don't see how you could use this for any other use (as all mail wil be sent to your ISP email then)
 
Old 08-05-2005, 02:14 PM   #8
Matir
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You know, it really bothers me that ISPs are blocking things like that. I guess they're afraid someone will run an open relay... it's really a shame that society can't have the maturity to say that people should be responsible for their own actions, and nobody else's. </rant>
 
Old 08-05-2005, 03:07 PM   #9
Half_Elf
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Quote:
it's really a shame that society can't have the maturity to say that people should be responsible for their own actions, and nobody else's.
<FLAME>
I would agree with this about real life (you know, life, laws and that kind of thing) but not about computers... There should be licence about right to use a computer, don't you feel there is just too much dummer using a computer? It's getting worst and worst with every version of windoze. Spywares exist because 75% of the users never read the screen, they just press next next next finish. Most of time, there is a little check "yes I would like to install buzzy buddy crap on my computer and receive tons of ads" but no one bother to read this. With the new popularity of linux, it's even worst, you give _server_ tools to some people that shouldn't even be using winXP. A lot of distro come with a SMTP server preintalled and most newbie _never_ update their system (and eventually get rooted)... I am glad that ISP DO block this damn port.
</FLAME>
 
Old 08-05-2005, 04:54 PM   #10
Matir
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Half_Elf: Honestly, I partially and disagree with you. But I won't say any more than that to avoid turning this thread into an argument over personal responsibilities.

My apologies to the OP for getting it headed in that direction at all.
 
Old 08-05-2005, 07:09 PM   #11
ultrax
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To answer your question it's a personal use and also a learning purpose.
I think using "mail reflector" is a solution. Is there any other providers than no-ip.com who are offering that service?
I actually use the smtp of my ISP to send emails to the outside...

thanks for your advice!


Quote:
Originally posted by Half_Elf
most ISP are blocking port 25, at least, all canadian ones do this.
Out of the "external mail forwarder" or the " mail reflector" I doubt there is any others way to bypass this. If you want to install a SMTP server for learning purpose or for personnal use, you could install a local mail server and "rewrite" new "FROM:" header to your outgoing mail before sending this to your ISP mail server (which may be open to their inside network... at least my ISP is like this). Making the FROM statement to be your ISP real mail would allow you to send mail from your local server and some tweak may allow you to download your mail from their pop to your local server. But this would only be useful if you plan to teach yourself the art of SMTP serving I don't see how you could use this for any other use (as all mail wil be sent to your ISP email then)
 
Old 08-05-2005, 07:14 PM   #12
ultrax
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It's really interessing to see my thread is turning into an argument for many of us.
That's also mean we're all concerning about this matter.
Feel free to impress yourself, I really don't mind u guys...

Quote:
Originally posted by Matir
Half_Elf: Honestly, I partially and disagree with you. But I won't say any more than that to avoid turning this thread into an argument over personal responsibilities.

My apologies to the OP for getting it headed in that direction at all.
 
Old 08-05-2005, 08:20 PM   #13
Matir
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I'm just of the mindset that I paid for the bandwidth, so I should get to play with the bandwidth.
 
Old 08-05-2005, 08:36 PM   #14
mhallbiai
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without knowing your isp i can not tell you if they offer this or not but it would be worth looking/asking.

my isp blocks ("filters") port 25. however, they do offer an 'opt-out' for this "filtering" on port 25. i found it on their _abuse_ page of all places. after submitting the opt-out request, 24hrs later a confirmation email from them, and a reset of the modem, bingo, i can send and receive email from my system without having to use their smtp servers

hope this helps
 
Old 08-05-2005, 09:16 PM   #15
Matir
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That's really odd. Then again, I guess it keeps the idiots protected.
 
  


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