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I'm running a multi-server and I have some issues with SMTP, mainly I'm trying to test my mail accounts on a windows machine with outlook express.
First let me say that configuring DNS was way over my head and I didn't have enough time, so i bought a custom DNS account from dyndns.org. I have a CNAME set up as "mail.mydomain.net" referring to "mydomain.net."
Locally on my machine, everything works fine. I can send and receive mail from my account using mutt.
doing a "telnet localhost 110" and "telnet mail.mydomain.net 110" produce the same result, qpopper is mentioned and it works fine.
Here's the issue though, "telnet localhost 25" shows exim running on that port and whatnot, and it works fine on localhost.
However, "telnet mail.mydomain.net 25" connects to my machine
and it looks to be that it's connected to my machine, but nothing is mentioned about exim and whatnot, and no commands produce any results, it's almost like it's connected to my box, but nothing more.
I use qpopper as a pop server, which works fine. In Outlook I can receive mail from "mail.mydomain.net" under my username. Cool...
But once again, when I try to send mail, outlook says it's connected, but it eventually times out. and produces this error:
The message could not be sent because one of the recipients was rejected by the server. The rejected e-mail address was 'foo@bar.com'. Subject 'test', Account: 'mail.mydomain.net', Server: 'relst8.net', Protocol: SMTP, Server Response: '550 relaying to <foo@bar.com> prohibited by administrator', Port: 25, Secure(SSL): No, Server Error: 550, Error Number: 0x800CCC79
And /var/log/exim/rejectlog:
2003-01-19 11:05:47 refused relay (host) to <foo@bar.com> from <user@mydomain.net> H=linksys_router (winbox) [192.168.1.1]
------------------------------------------------------------------------------
Yes, i should also mention that i'm behind a router, and i have ports 110 and 25 fowarded to my server machine...
This is really puzzling, and i think the solution might be simple, but it doesn't look it so far!
Hi. The problem is as in the mesage from the SMTP server: the relaying. For some of the smtp servers (I do not know which one you use) after installation the sever accepts only the messages which are sent to local accounts only (local means the accounts defined as having mail boxes at machine running smtp server).
Basic smtp protocol allows anybody to send mails to anybody using your smtp server. So not only the mails to you are accepted. I can send a mail to my friend using your server. Such mails will be accepted by your server and send to the proper destination. This process is called relaying. To prevent for that (the spammers use this technique) it can be switched off.
So read more about server settings and relaying. And remeber that if you just switch on mails relaying you will find out for the moment that 99% of the server activity will be spam retransmission and for the moment your server will be treated for anybody as a spam server.
OK, i'm using exim for my smtp server i guess, at least in inetd.conf, the setting for smtp uses exim.
I'm finding a lot of information on sendmail and relaying and such, and not as much on exim. And the information for it seems to be in foreign languages that i'm not familiar with. %/
I guess i'll have to keep looking.
If it means anything else, I initially set up exim to use my isp's server for mail. Would this do any interfereing?
And another issue is MX, which i'm kinda clueless about.
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