To send e-mail, you will need to specify an SMTP (outgoing e-mail) server in your e-mail reader.

As a pair Networks customer, you may use our SMTP service as long as you are not in violation of our policies (i.e. not sending out spam). Also, please do not use our mail server for:

  • Sending out large quantities of e-mail to multiple recipients (i.e. running a mailing list). Please consider using pairList instead.
  • Sending large attachments.
  • Sending e-mail from addresses not affiliated with your accounts and services obtained from pair Networks.
  • Spam.

SMTP Server Name

If your Web hosting account was created before June 1, 2011, your SMTP server is, where “###” is your mail server number. Your mail server number can be found in the ACC.

If your Web hosting account was created on or after June 1, 2011, your SMTP server is, where “username” is replaced by your pair Networks username.


We require SMTP Authentication, also know as SMTP AUTH. With SMTP AUTH, you connect your e-mail client directly to your e-mail hosting server to send e-mail using your mailbox username and password to ensure the validity of outgoing e-mail.

Outgoing e-mail configuration using SMTP AUTH is simple: just use the same hostname, username, and password settings that you use to retrieve your incoming e-mail. The specific settings you should use for a particular mailbox are available in the Account Control Center (ACC) E-Mail Management interface. View the mailbox you’re interested in, and the proper Username and Hostname settings will be displayed.

SMTP AUTH is activated on all standard outgoing e-mail ports, so the default port number should work without modification. If your e-mail client has an option to use SSL/TLS or STARTTLS, you must turn it on. To prevent your mailbox username and password from being compromised, we require the use of SSL/TLS or STARTTLS encryption for all SMTP AUTH requests.

File Size Limits

Please also note that the file size limit when sending mail is 40 MB. This limit is for the message body and the sum of all attachments in their encoded state. When a file is encoded for e-mail, it can increase the size of the file significantly. With a limit of 40 MB, you may only be able to attach files around 35 MB (before encoding). The exact size of the file will depend on the contents of the file itself.

Outgoing E-Mail Ports

Many ISPs, including America Online, EarthLink, and MSN, will not allow access to an external SMTP server. This is most commonly implemented by blocking traffic to port 25, the SMTP port. If your e-mail reader supports it, you may work around this restriction by using port 465 or 587 instead.

If your ISP filters port 25 and your e-mail reader cannot use a different port, or if your ISP filters by some other means, you will not be able to use our SMTP service. If you are a subscriber of one of these services, please contact your ISP for assistance in using SMTP to send e-mail.


If you are using SSL and your account was created prior to June 1, 2011, you must use to avoid secure certificate mismatch warnings. “X” should be replaced with your server number.

For accounts created after June 1, 2011, you must use to avoid secure certificate mismatch warnings. “Username” should be replaced with your main account username.

The default port for SSL with SMTP is 465. However, most e-mail reader programs will use this port automatically, so you probably do not need to set this port yourself.

For help with your e-mail reader, please see the Using a POP/IMAP e-mail reader article.