Unable to send email

SMTP, Port: 25, Secure(SSL): No, Error Number: 0x800CCC0B

If you can not send email using mail.yourdomainname.com as your SMTP server,
it may be because your ISP is blocking port 25 on their network, used for sending outoing mail via the SMTP protocol.
In this instance, we recommend using your ISPs outgoing mail server, which can be obtained from your ISP.

Please check with your ISP for their outgoing mail server settings (SMTP) and adjust in your email program under email account setup .


If you are using Outlook Express

Solution Configuring an email client requires that you enable
authentication for all the outgoing emails. To do so follow the steps given below

1. Open the Outlook Express.
2. Go to Tools -> Accounts
3. Select the email account name from the Mail tab of Internet Account Window.
4. Click on the Properties.
5. Go to the Servers Tab.
6. Check the option My Server Requires authentication.
7. Click on Apply button
8. Click on Close button to close the Internet Mail Account Window

http://kb.mozillazine.org/Cannot_send_mail

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Why can I receive email, but not send any?

If you can receive mail and cannot send mail then there can be two reasons.

1. Authentication Failed You do need to authenticate before you can relay mail.
This means you will need to use SMTP Authentication in your mail client.

2. ISP is Blocking Port 25 If your ISP is blocking port 25, you may not be able to send email.
Some ISPs do this so that you are forced to use their email servers when sending email, as an attempt to prevent spam.

In order to test that the SMTP (outgoing) mail server is functioning properly, you will need to use telnet.
You may use any telnet client that will allow you to telnet to port 25 on your domain.
This can usually be done by simply trying to point your browser to telnet://daveonline.ca:25
or From your windows machine.
Start-->Run-->Cmd
telnet daveonline.ca 25

You will get a response like below from the mail server.

# telnet daveonline.ca 25
Trying 70.85.231.190...
Connected to daveonline.ca (70.85.231.190).
Escape character is '^]'.
220-mercury.nocstation.info ESMTP Exim 4.52

If you are using a Linux machine, then you can type in the command below to check if you are able to connect to the
mail server port 25
telnet daveonline.ca 25

Please check with your ISP for their outgoing mail server settings (SMTP) and adjust in your email program under
email account setup .