How to Whitelist in Proofpoint

If you're utilizing Proofpoint's spam filtering, you can whitelist KnowBe4 to allow our simulated phishing test emails and training notifications through to your end users.

If you're using the Proofpoint Essentials suite of services, see the below articles instead:

• General Proofpoint Essentials Whitelisting: How to Whitelist an IP Address to Bypass Spam Filtering
• If you want to spoof your own domain using KnowBe4: Bypass Imposter Email Detection

When you're ready to whitelist in Proofpoint, follow the below instructions:

1. From your Proofpoint admin center, navigate to Email Firewall, then Rules.
2. Be sure to select the "On" radio button for Enable, under Rule Settings.
3. Name your rule ID something such as "KnowBe4 Whitelisting by IP Address," and provide a description such as "KnowBe4 Phishing and Training emails." 

4. In the "Condition" section you will whitelist KnowBe4 by our IP addresses using the "Add Condition" button. Below you can find our IP addresses for phishing and training emails.

5. Under Dispositions, change the Delivery Method from the default selection to Deliver Now.

6. Be sure to save your rule and allow time for this new setting to propagate before testing. 

Back to Top

How to Prevent Proofpoint from Bouncing Emails 

If some of your phishing security test (PST) emails are bouncing with an error message of 
"Sender address rejected: Domain not found (in reply to RCPT TO command)",
follow the instructions below to resolve this issue.

1. Navigate to your KnowBe4 account settings by clicking on your email address in the top-right corner and then click "Account Settings". 
2. Scroll down to the Phishing section and ensure that the "Disable return path header" option is not enabled (see below). 

3. Be sure to save this change by clicking the "Update Account Info" button at the bottom of the page.
4. In order to confirm this change will prevent Proofpoint from causing your PST emails to bounce, test this change by sending a test campaign to yourself or a limited number of users before sending it to a larger group. 

Still need assistance? Submit a support ticket and we can help.