How To Send Email Using CritSend's SMTP Relay

Two easy steps to send your CritSend mail:

Step 1: Configure your mail server or mail client.
Step 2: Test & send.

If instead you wish to send through CritSend using our SOAP API, see CritSend's API doc page for API info and examples.

Step 1: Configure

Basic Setup Info

Point to CritSend's SMTP relay using the following parameters:

  • Server:* smtp.critsend.com
  • Port: 25 or 587
  • Username: [your CritSend username]
  • Password: [your CritSend password]
  • Encryption: Plain Text
  • *Amazon Web Services customers can user our server within EC2: aws-smtp.critsend.com
  • Because you are connecting to a distributed cluster, it is also a good idea to set your software or app to retry automatically if you receive a connection error, and to re-resolve the domain if you have a failed attempt.

Config file examples for common Mail Servers

sendmail | postfix | exim | qmail

How to send emails in your preferred language

PHP | ruby | .net | python | java

Step 2: Test & Send

You are now ready to send mail. Send some test messages.

You can test the quick & easy way using our web-based Test Delivery Page.

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