Sender domain policy FAQs

Overview

This article explains DreamHost's Sender domain policy, which was created to protect the reputation of DreamHost’s mail servers and provide a stable and reliable service to customers.

Background

DreamHost’s sender domain policy ensures email that is sent from your website is legitimate. This policy requires two things:

• You must use a FROM address that's on the same domain you're sending email from.
• The email must be hosted at DreamHost.

When this policy applies

This policy applies to all DreamHost-hosted emails, including those being sent directly from the web server, most often through a PHP contact form.

When this policy does not apply

If you use SMTP authentication with an external mail provider, this policy DOES NOT apply to you. You can use SMTP authentication in a few ways:

• Coding it directly into your form
• Using a plugin that uses SMTP authentication

Additionally, this policy does not apply to DreamHost's VPS and Dedicated Servers. Emails sent from a VPS or Dedicated Server using PHP's mail(), Sendmail, or SMTP via localhost, are sent directly through the server's postfix mail system and go out to the recipient without passing through any other DreamHost server.

Examples of FROM addresses

The following specifies email addresses this policy allows, as well as addresses that will be rejected by it. 

Acceptable FROM addresses

How the email is sent	FROM address used	Explanation of address
SMTP through a mail client	username@example.com	Uses your normal email address while sending email via SMTP
Through a webform on a website named example.com	username@server.dreamhost.com	Uses your web server as the hostname. This works but may look strange. An example would be contact@iad1-shared-e1-09l.dreamhost.com.
Through a webform on a website named example.com	username@example.com	This works since the email is on the same domain sending the email. However, the email MUST be hosted at DreamHost.
Through a webform on a website named example.com using SMTP authentication.	Any address you like	When SMTP authentication is used, the mail is not sent from the web server. It's sent directly through the SMTP mail server you specify. You can provide SMTP credentials for any email address you wish to send FROM. This is the recommended way to send email in a form.

Blocked FROM email addresses

Emails should not be sent with a FROM address hosted somewhere else. For example:

• user@comcast.net
• user@gmail.com

If you need to use any address not hosted with DreamHost as your FROM address, you must use SMTP authentication.

How to view rejected emails

Blocked emails are returned to the sender as an 'undelivered' bounced email and may be stored in the Maildir/new folder on the web server. You have several options to view this information.

Option 1 — Using FTP

1. Log into your server via FTP.
2. Confirm you're in your user's directory.
3. In the right pane, click into the /Maildir folder.

   

4. Click into the /new folder to view a list of email files.
5. Right-click and open a file in a text editor to view its contents and the reason it failed to send.

   Blocked email displays the following error message:

   5.7.1 Sender domain not allowed
   

Option 2 — Contacting support

DreamHost support can also check the server mail logs for any errors that may have been recorded. When you Contact Support, provide as many details as possible about the email to research. Here are the minimum amount of details support needs to assist:

• Date and time it was sent (including timezone)
• Email addresses it was sent TO
• Email address it was sent FROM
• The website URL for the web form that is not functioning properly

Option 3 — Creating a custom script

Instead of manually checking the folder on your server, you can create a script that automatically emails you whenever an email is rejected. See this article for further details.

See also

• Sender domain policy and spoofing overview
• How to spoof in your CMS or web application
• Send PHP mail via SMTP