Sending mails not working

Posted on 2006-04-10
Medium Priority
Last Modified: 2010-04-18
I installed mail server on our Win 2003 server. I receive e-mails but can not send. I see 0x800ccc78 error message. I am thinking that port 25 might be closed by our ISP. Is there any easy way or command to check for it?
Question by:ugurde
  • 3
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Accepted Solution

Chris Dent earned 1000 total points
ID: 16418234

If you know a server you want to send to then you can use Telnet. i.e.:

C:\> Telnet <Mail Server you want to send to> 25

Then you can use the SMTP Commands (and it's not at all forgiving of typing mistakes here):

mail from: <your e-mail address>
rcpt to: <recipient's e-mail address>
subject: Testing

(Enter then "." then Enter to finish the body of the mail).

If you get as far as being able to do Helo then Port 25 isn't being blocked.


LVL 23

Assisted Solution

TheCleaner earned 1000 total points
ID: 16418244
Yes, that is very typical.  You will need to configure your OUTBOUND mail to go through the ISP's outbound mail server.  Basically the ISP says that any emails destined out port 25 must be sent through their outgoing mail server, not through your own.  This helps cut down on them being accused of allowing spam/relaying.

So, your incoming may be - mail.domain.com

but outgoing would be - mail.YOURISP.com  (or whatever their outgoing SMTP server is) port 25.

Just go to the ISP's website and it should be in the support section there, or give them a call.
LVL 23

Expert Comment

ID: 16418269
By that way, forgot to post about the error message:  http://www.howtoadvice.com/BlockedSMTP

Author Comment

ID: 16420341
I called the company and learned that I had to type their mailserver address. Thanks for your help.
LVL 23

Expert Comment

ID: 16420404

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