Summary
Verizon Media PH01 errors occur primarily due to email content being flagged as potential phishing. Causes include compromised accounts, links to malicious sites, suspicious content, poor IP reputation, and issues with email authentication protocols (SPF, DKIM, DMARC). Resolution involves regular security audits, content scanning, maintaining an up-to-date understanding of email best practices, avoiding URL shorteners, implementing strict DMARC policies, ensuring SPF records are accurate, monitoring sender reputation, cleaning email lists, and avoiding sudden spikes in sending volume. Issues stemming from third-party senders may also cause this error.
Key findings
- Phishing Detection: PH01 errors are triggered when Verizon Media's filters identify potential phishing content in emails, either within the email itself or in linked websites.
- Account Compromise: Compromised sender accounts can send phishing emails, which leads to the contamination of IP addresses and authentication methods, triggering PH01 errors.
- Authentication Importance: Correct implementation of SPF, DKIM, and DMARC is crucial for establishing trust and reducing the likelihood of being flagged for phishing.
- Reputation Matters: Poor IP reputation due to spam complaints or presence on blacklists can trigger PH01 errors; monitoring and maintaining a good sender reputation is essential.
- Content Is Key: Suspicious links, URL shorteners, and certain wording in email content can trigger phishing filters and result in PH01 errors.
- Third-Party Impact: When sending via third-party services (e.g., Iterable), their actions or blacklistings can impact your deliverability and cause PH01 errors.
Key considerations
- Regular Security Audits: Conduct regular security audits to identify and address potential vulnerabilities that could lead to account compromises and malicious email sends.
- Content Scanning Implementation: Implement content scanning tools to automatically detect and remove suspicious elements before sending emails.
- Best Practice Education: Stay informed about the latest email authentication and content creation best practices to avoid triggering phishing filters.
- Link Review: Thoroughly review all links within emails to ensure they are not pointing to phishing sites, and avoid the use of URL shorteners.
- DMARC Policy Enforcement: Implement and enforce a strict DMARC policy (p=reject) to prevent unauthorized use of your domain.
- SPF Record Accuracy: Ensure your SPF record accurately lists all authorized sending sources to prevent authentication failures.
- Reputation Monitoring Vigilance: Regularly monitor your sender reputation using tools like Google Postmaster Tools and Sender Score to identify and address potential issues promptly.
- List Hygiene Discipline: Maintain a clean email list by regularly removing inactive or invalid addresses to improve engagement and sender reputation.
- Sending Volume Management: Manage your email sending volume to avoid sudden spikes, which can trigger spam filters.
- Third-Party Assessment: Ensure that you regularly assess your third party senders. Assess any issues and blacklistings of those services.
What email marketers say
11 marketer opinions
Verizon Media PH01 errors typically arise from issues related to potential phishing content, poor sender reputation, or compromised authentication. Solutions include checking URLs against blacklists, ensuring proper SPF, DKIM, and DMARC configuration, reviewing email content for suspicious elements, monitoring and improving IP reputation, and implementing feedback loops. Shared hosting environments, URL shorteners, and sending volume also contribute to these errors. Regular list cleaning and avoiding sudden sending spikes help maintain a positive sending reputation.
Key opinions
- Phishing Content: PH01 errors are often triggered by email content that resembles phishing attempts, including suspicious links, URL shorteners, and certain language patterns. Regularly scan and review content to avoid being flagged.
- Authentication: Incorrect or missing SPF, DKIM, and DMARC records can lead to deliverability issues, including PH01 errors. Properly configuring these records is essential for establishing trust with Verizon Media.
- Sender Reputation: A poor IP reputation or a presence on blacklists can trigger PH01 errors. Monitoring and improving IP reputation is critical, which includes addressing spam complaints and practicing good sending hygiene.
- Shared Hosting: Using a shared hosting environment can negatively impact your sending reputation due to the actions of other users. Consider dedicated IPs or reputable email sending services.
- List Hygiene: Poor list hygiene, including sending to inactive or invalid addresses, can damage your sender reputation and increase the likelihood of PH01 errors. Regularly clean your email list to improve engagement.
- Third-Party Issues: Issues from Third Parties can effect your email deliverability. If you send through a third party such as Iterable it could effect your deliverability.
Key considerations
- Content Review: Regularly review email content for elements that might be flagged as suspicious, and make necessary adjustments to avoid PH01 errors.
- Authentication Setup: Ensure that SPF, DKIM, and DMARC records are correctly configured and up to date to authenticate your sending domain and improve deliverability.
- Reputation Monitoring: Monitor your IP reputation using tools like Sender Score and address any issues promptly to maintain a positive sending reputation.
- Feedback Loops: Set up feedback loops (FBLs) with Verizon Media to receive reports on spam complaints and take corrective actions to improve your sending practices.
- Sending Volume: Avoid sudden spikes in email sending volume and spread out your sends to maintain a consistent sending reputation and prevent triggering spam filters.
- Third Party Services: Be sure to check that all third party services you use are operating correctly and not causing any issues that might effect your email deliverability and reputation.
Marketer view
Email marketer from Email Geeks shares that they saw a client with same SURBL on Yahoo last week and to be sure to delist with SURBL and Norton. It appears that they made a change to their algorithms and a series of clients are showing up flagged, since it is happening at multiple ESPs. It appears to have lifted on its own on Sunday and Yahoo said they lifted before Surbl did
10 Oct 2022 - Email Geeks
Marketer view
Email marketer from Reddit suggests ensuring that your sending domain has proper authentication records (SPF, DKIM, DMARC) configured correctly, as this helps to establish trust with Verizon Media and reduce the likelihood of being flagged as phishing.
28 Feb 2024 - Reddit
What the experts say
3 expert opinions
PH01 errors in Verizon Media typically indicate that the email content is flagged as potential phishing. Causes include compromised accounts sending malicious emails, links to phishing sites, or email content that resembles phishing attempts. Resolving these errors involves content review, security audits, and staying updated on Verizon's evolving filtering systems.
Key opinions
- Phishing Identification: PH01 errors are triggered when Verizon Media's filters detect potential phishing content in emails.
- Compromised Accounts: Compromised accounts can send phishing emails, leading to contamination of IP addresses and authentication methods, triggering PH01 errors.
- Content Matters: Suspicious links and wording in email content can trigger phishing filters, resulting in PH01 errors.
- Evolving Systems: Verizon's filtering systems are continually updated, requiring ongoing adaptation of email authentication and content creation practices.
Key considerations
- Regular Audits: Conduct regular security audits to identify and address potential vulnerabilities that could lead to account compromises.
- Content Scanning: Implement content scanning tools to detect and remove suspicious elements before sending emails.
- Update Knowledge: Stay informed about the latest email authentication and content creation best practices to avoid triggering phishing filters.
- Link Review: Check all links to ensure they do not point to phishing sites. Avoid using URL shorteners.
Expert view
Expert from Word to the Wise shares that Verizon's filtering systems are constantly evolving. Staying up-to-date on best practices for email authentication and content creation can help you avoid PH01 errors.
24 Jul 2023 - Word to the Wise
Expert view
Expert from Spam Resource explains that checking your email content for elements that commonly trigger phishing filters, such as suspicious links or wording, is a good first step in resolving PH01 errors. They recommend using tools to scan content before sending.
2 Jun 2025 - Spam Resource
What the documentation says
5 technical articles
Verizon Media PH01 errors arise from suspected phishing content detected by their filters, stemming from email content or linked websites. Addressing this involves robust email authentication using SPF, DKIM, and DMARC to prevent spoofing, ensuring accurate SPF records covering all sending sources, and monitoring sending reputation via tools like Google Postmaster Tools for broader email health insights. Implementing a strict DMARC policy helps prevent unauthorized domain use for phishing.
Key findings
- Phishing Flagging: PH01 errors signify that Verizon Media's filters have flagged email content or linked websites as potential phishing attempts.
- DMARC Policy: A strict DMARC policy (p=reject) helps to prevent unauthorized use of your domain for phishing and spoofing.
- SPF Configuration: Incorrect or incomplete SPF records can contribute to PH01 errors; ensuring accurate records is crucial.
- DKIM Signatures: Correct DKIM implementation verifies the sender's identity and ensures content integrity, improving deliverability.
- Reputation Monitoring: Monitoring sending reputation using tools like Google Postmaster Tools provides a broader view of email health and helps identify issues.
Key considerations
- Content Scrutiny: Examine email content and links for potential phishing red flags before sending.
- DMARC Implementation: Implement and enforce a strict DMARC policy to protect your domain from unauthorized use.
- SPF Accuracy: Ensure your SPF record accurately lists all authorized sending sources to prevent authentication failures.
- DKIM Setup: Correctly implement DKIM signatures to verify the sender's identity and message integrity.
- Reputation Awareness: Regularly monitor your sending reputation to proactively identify and address potential deliverability issues.
Technical article
Documentation from DMARC.org explains that implementing a strict DMARC policy (p=reject) can help prevent unauthorized use of your domain for phishing and spoofing, which reduces the chance of your emails being flagged with a PH01 error when legitimate emails are sent.
5 May 2025 - DMARC.org
Technical article
Documentation from Verizon Media Postmaster explains that a 554 PH01 error indicates that the email was not accepted for policy reasons, specifically due to suspected phishing content. The error occurs when the email content or linked websites are flagged as potential phishing attempts by Verizon Media's filters.
21 Dec 2021 - Verizon Media Postmaster
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