Whitelisting - Internal and Private Domain Deliverability Issues

When you encounter deliverability issues at a private domain (or your own domain for that matter), you may need to have your sending IP and/or sending domain whitelisted. Private email domains tend to have more aggressive filters in place when compared to other large email providers (such as Gmail, AOL, Yahoo!, etc.). There are usually two ways in which an organization should think about whitelisting:

  • Whitelisting your own organization.
  • Whitelisting at other private domains.

Let's look at each of these.

Whitelisting at Your Own Organization

When you use an outside mail server (such as Informz) to send mail on your behalf, you commonly see deliverability issues when receiving mail at your organization. This is because your mail server can identify mail sent outside of its system (using your sending domain) as being  "suspicious" and either quarantine or flag as spam. 

Reach out to your IT department prior to sending through Informz to have them whitelist your Informz IPs and possibly our bounce address "informz.net." You can find your IPs by logging into your account and navigating to Admin > System Settings and then scrolling to the bottom of the screen.

If you continue to have issues receiving mail sent from Informz internally at your organization, it may be wise to reach out to your IT department to see if there is another filter preventing mail from being delivered (this could be content, sender authentication, too much mail sent at once, etc.).

Whitelisting at Other Private Domains

If you find that mail is not being delivered to the recipients' inbox at a private domain, then you may want to reach out to the domain owner or postmaster to request to whitelist your Informz publish IP, informz.net, and/or your "from" address.


Keep in mind that whitelisting does not guarantee mail will be delivered to the inbox. Whitelisting is done by the mail receiver and if the sender is not following best practices, the whitelisting in place may be ignored.