Why are Google Workspace emails not delivering to Proofpoint?

Summary

Google Workspace email delivery to Proofpoint can fail due to several reasons: domain/content issues, cold outreach practices, SPF/DKIM/DMARC misconfigurations (especially with alias domains), poor list hygiene, sender reputation problems, and aggressive filtering/throttling by Proofpoint. Solutions involve improving authentication, content, list hygiene, and sender reputation, using feedback loops, adjusting sending volumes, and potentially whitelisting the domain/IP.

Key findings

  • Authentication Issues: SPF/DKIM/DMARC misconfigurations, particularly with multiple domains, are a primary cause of delivery failure.
  • Domain/Content Problems: Issues with the domain itself or the content triggering spam filters significantly impact deliverability.
  • Sender Reputation: A poor sender reputation, based on IP, domain, and email content, can lead to emails being blocked.
  • List Hygiene Matters: Poor list hygiene (spam traps, invalid addresses) significantly lowers deliverability to Proofpoint.
  • Proofpoint Filtering: Proofpoint's aggressive filtering rules and potential throttling mechanisms contribute to delivery problems.
  • PTR Records Important: Mismatched PTR records raise red flags and affect deliverability.
  • Feedback Loops Vital: Lack of participation in feedback loops limits the ability to identify and address spam complaints.
  • Cold Outreach Hurts: Cold outreach practices are detrimental to sender reputation and deliverability.

Key considerations

  • Authentication Checks: Verify and correct SPF, DKIM, and DMARC records, ensuring they are properly configured for all sending sources.
  • Content Optimization: Review email content for spam-like keywords, excessive links, and suspicious attachments. Optimize accordingly.
  • Reputation Monitoring: Continuously monitor domain and IP reputation using available tools and take steps to improve it.
  • List Cleaning: Regularly clean and maintain mailing lists to remove inactive subscribers, spam traps, and invalid addresses.
  • Feedback Loop Implementation: Implement feedback loops with major mailbox providers to receive and act on spam complaints.
  • PTR Record Alignment: Ensure PTR records match the sending IP addresses.
  • Whitelist Request: If issues persist, request the recipient's IT department whitelist your domain or IP address.
  • Avoid Cold Outreach: Minimize or eliminate cold outreach practices to improve deliverability and sender reputation.
  • Check Proofpoint Logs: Investigate Proofpoint's logs to find out the exact reason why emails are being rejected or filtered.
  • Adjust Sending Volume: Avoid sending huge quantities of emails in a short time to prevent throttling from Proofpoint.

What email marketers say
7Marketer opinions

Google Workspace emails may fail to deliver to Proofpoint due to various reasons, including SPF/DKIM/DMARC misconfigurations, especially when using multiple domain aliases. Proofpoint's aggressive filtering rules, content-based spam triggers, mismatched PTR records, poor IP reputation, and email throttling can also cause delivery issues. Whitelisting the sending domain/IP or checking Proofpoint's logs for rejection reasons can help resolve the issue.

Key opinions

  • Authentication: Incorrect SPF/DKIM/DMARC settings are a common cause, particularly with multiple domain aliases.
  • Filtering: Proofpoint's stringent filtering rules can block emails.
  • Content: Spam-like content, excessive links, or suspicious attachments can trigger Proofpoint's filters.
  • PTR Records: Mismatched PTR records can negatively affect delivery.
  • IP Reputation: A poor IP reputation due to past spam activity can lead to blocked emails.
  • Throttling: Sending a high volume of emails in a short period can trigger Proofpoint's throttling mechanisms.

Key considerations

  • Verify Authentication: Double-check SPF, DKIM, and DMARC records for proper configuration, especially when using multiple domains.
  • Check Proofpoint Logs: Examine Proofpoint's logs to identify specific rejection reasons.
  • Optimize Content: Review email content for spam triggers and optimize accordingly.
  • Match PTR Records: Ensure PTR records match the sending IP addresses.
  • Monitor IP Reputation: Regularly monitor IP reputation and take steps to improve it if necessary.
  • Adjust Sending Volume: Adjust email sending volume to avoid triggering throttling mechanisms.
  • Request Whitelisting: Consider asking the recipient's IT department to whitelist your domain or IP address.
Marketer view

Email marketer from Email Marketing Forum suggests that Proofpoint may have aggressive filtering rules. He also suggests checking Proofpoint's logs for specific rejection reasons and working with the recipient to whitelist the sending domain or IP address.

August 2021 - Email Marketing Forum
Marketer view

Email marketer from Reddit explains that common causes include SPF/DKIM/DMARC misconfiguration, especially if multiple domains are used as aliases. They recommend checking these settings and ensuring proper authentication is in place.

February 2023 - Reddit
Marketer view

Email marketer from StackOverflow emphasizes the importance of PTR records (reverse DNS) matching the sending IP addresses. Mismatched PTR records can raise red flags with Proofpoint's filtering system.

November 2023 - StackOverflow
Marketer view

Email marketer from LinkedIn discusses the importance of IP reputation. If the sending IP address has a poor reputation due to previous spam activity, Proofpoint is more likely to block emails. Monitor IP reputation and take steps to improve it if necessary.

April 2023 - LinkedIn
Marketer view

Email marketer from SuperUser mentions Proofpoint may be throttling emails if the sender is sending a large volume of emails in a short period. Adjust sending volume to avoid triggering throttling mechanisms.

May 2023 - SuperUser
Marketer view

Email marketer from Mailflow Expert Blog mentions that if the email content triggers Proofpoint's spam filters, emails might not be delivered. They advise reviewing email content for spam-like keywords, excessive links, or suspicious attachments.

August 2024 - Mailflow Expert Blog
Marketer view

Email marketer from Quora suggests contacting the recipient's IT department and requesting that your domain or IP address be whitelisted in Proofpoint. Whitelisting creates an exception to bypass the Proofpoint's filtering rules.

May 2023 - Quora

What the experts say
8Expert opinions

Google Workspace emails may be blocked by Proofpoint due to domain/content-related issues, particularly when combined with cold outreach and lack of SPF alignment for alias domains. Poor list hygiene and sender reputation also significantly impact delivery. Setting up feedback loops (FBLs), verifying authentication, and correct DMARC setup are crucial steps for resolving these issues.

Key opinions

  • Domain/Content: The core issue is likely related to the domain or the email content itself.
  • Cold Outreach: Cold emailing practices negatively impact deliverability.
  • SPF Alignment: Lack of SPF alignment, especially for alias domains in GSuite, causes delivery problems.
  • List Hygiene: Poor list hygiene, including spam traps and invalid addresses, significantly reduces deliverability to Proofpoint.
  • Sender Reputation: Proofpoint heavily relies on sender reputation; a bad reputation results in blocked emails.
  • Feedback Loops: Not utilizing feedback loops hinders the ability to identify and remove problematic subscribers.
  • Authentication: Improperly configured or missing DMARC and broken authentication hurts deliverability.

Key considerations

  • Address Domain/Content: Investigate and resolve domain and content-related issues that might trigger Proofpoint's filters.
  • Avoid Cold Outreach: Refrain from cold emailing practices that harm sender reputation.
  • Implement SPF Alignment: Ensure proper SPF alignment, particularly for alias domains, in GSuite settings.
  • Improve List Hygiene: Regularly clean mailing lists to remove spam traps and invalid addresses.
  • Monitor Sender Reputation: Monitor sender reputation using tools like SenderScore and Talos to identify and address issues.
  • Setup Feedback Loops: Sign up for feedback loops (FBLs) with major mailbox providers.
  • Check Authentication and DMARC: Setup DMARC correctly, and ensure authentication is working correctly.
Expert view

Expert from Email Geeks says that without a rejection message, he agrees with Matt V that it is likely domain/content related.

June 2021 - Email Geeks
Expert view

Expert from Word to the Wise (Blog) shares to check that your authentication is working, and make sure you have set up dmarc correctly.

December 2022 - Word to the Wise
Expert view

Expert from Email Geeks shares that lack of SPF alignment for alias domains on GSuite is a common pain point, even without cold leads.

March 2022 - Email Geeks
Expert view

Expert from Word to the Wise (Blog) shares to make sure you've signed up for feedback loops (FBLs) with major mailbox providers, including those that share data with Proofpoint. FBLs provide valuable information about spam complaints, allowing you to quickly remove problematic subscribers from your lists and prevent future delivery issues.

July 2022 - Word to the Wise
Expert view

Expert from Email Geeks suspects the client is doing cold outreach using that return path.

November 2024 - Email Geeks
Expert view

Expert from Email Geeks believes the issue is domain/content related.

March 2025 - Email Geeks
Expert view

Expert from Spam Resource (Blog) indicates that Proofpoint heavily relies on sender reputation metrics. Monitoring your domain and IP reputation using tools like SenderScore or Talos is crucial to identify and address any negative reputation issues that might be affecting delivery to Proofpoint recipients.

May 2023 - Spam Resource
Expert view

Expert from Spam Resource (MailingList) suggests that Proofpoint is very sensitive to list hygiene. Even a small percentage of spam traps or invalid addresses can significantly impact delivery rates. Regularly cleaning your mailing lists and removing inactive or problematic addresses can improve deliverability.

May 2023 - Spam Resource

What the documentation says
6Technical articles

Google Workspace emails may be blocked by Proofpoint due to issues with email authentication (SPF, DKIM, DMARC), poor sender reputation based on IP, domain, and content, and exceeding email sending limits, particularly to large groups. Correctly configuring SPF records to include all Google Workspace sending sources, ensuring DKIM is enabled, setting up DMARC policies, and adhering to Google Workspace's sending limits are crucial for improving deliverability.

Key findings

  • SPF Configuration: Incorrect or incomplete SPF records can cause delivery failures.
  • DKIM Setup: Failure to properly configure and enable DKIM for email signing impacts deliverability.
  • DMARC Policy: Lack of a DMARC policy or an improperly configured policy affects email authentication and deliverability.
  • Sender Reputation: Proofpoint uses sender reputation (IP, domain, content) as a major factor in filtering decisions.
  • Sending Limits: Exceeding Google Workspace's sending limits can result in delivery problems, especially for large group emails.

Key considerations

  • Verify SPF Records: Ensure SPF records include all authorized sending sources for the domain, including Google Workspace servers.
  • Enable DKIM: Configure and enable DKIM for the domain to digitally sign outgoing emails.
  • Implement DMARC: Establish a DMARC policy to provide instructions to receiving mail servers on how to handle unauthenticated emails.
  • Monitor Reputation: Monitor sender reputation using available tools and address any identified issues.
  • Adhere to Sending Limits: Stay within the defined sending limits of Google Workspace, especially when sending to large recipient groups.
Technical article

Documentation from DKIM.org provides information on generating DKIM keys and adding them to the DNS records.

January 2024 - DKIM.org
Technical article

Documentation from DMARC.org offers information about DMARC policy setup.

September 2021 - DMARC.org
Technical article

Documentation from Proofpoint Support states that Proofpoint's system analyzes sender reputation based on factors like IP address, domain, and email content. Poor sender reputation can lead to blocked or filtered emails. They recommend monitoring reputation and addressing any issues identified by Proofpoint's system.

October 2022 - Proofpoint Support
Technical article

Documentation from Google Workspace provides guidelines regarding email sending limits, especially when sending to large groups of receipients.

October 2023 - Google
Technical article

Documentation from RFC-Editor specifies the correct syntax for SPF records, ensuring all Google Workspace sending IPs are correctly declared.

November 2021 - RFC-Editor
Technical article

Documentation from Google Workspace Admin Help shares to ensure that SPF records include all sending sources for your domain, including Google Workspace servers. Also, verify DKIM is properly configured and enabled for your domain to digitally sign outgoing emails.

December 2022 - Google Workspace Admin Help