Summary
When encountering blocked bounces after the first send with a new IP address, a multifaceted approach is necessary to ensure email deliverability. Begin by investigating potential Proofpoint issues, particularly for Apple domains, and contact icloudadmin@apple.com for assistance. Ensure your content is free of spam triggers and check your MX records. Initiate IP warming with a gradual increase in sending volume to build a positive reputation. Continuously monitor your sending reputation, bounce rates, and spam complaints, and segment your list to initially target engaged subscribers. Implement SPF, DKIM, and DMARC for authentication. Manage bounce rates through feedback loops, maintain high-quality content, and regularly clean your email list. Understand bounce message error codes, proactively monitor deliverability issues, and adhere to SMTP standards. Overall, addressing these factors helps improve deliverability and reduce the likelihood of bounces.
Key findings
- Proofpoint Issue: Blocked bounces could be due to Proofpoint, especially for Apple domains and one-off domains.
- IP Warming is Key: Gradually increase sending volume to build a positive sender reputation with ISPs.
- Monitor Reputation: Continuous monitoring of sending reputation, bounce rates, and spam complaints is essential.
- Segmentation Strategy: Start by sending emails to highly engaged subscribers to improve initial reputation.
- Authentication Matters: Implementation of SPF, DKIM, and DMARC is critical for email authentication.
- Manage Bounce Rates: Actively managing bounce rates through feedback loops is crucial for maintaining deliverability.
- Content is King: High-quality content free from spam triggers is vital for avoiding spam filters.
- List Hygiene: Regular cleaning of the email list improves deliverability and reduces bounce rates.
- Understand Bounce Errors: Analyzing bounce message error codes provides insights into the cause of delivery problems.
- Proactive Monitoring: Proactive monitoring of deliverability issues helps to identify and mitigate problems early on.
Key considerations
- Proofpoint Check: Verify if bounced domains use Proofpoint and address potential issues through their services.
- Warming Strategy: Implement a well-defined IP warming schedule to avoid triggering spam filters.
- Targeted Content: Ensure email content is relevant and engaging to avoid low engagement and high bounce rates.
- Authentication Configuration: Properly configure SPF, DKIM, and DMARC records to authenticate sending sources effectively.
- Bounce Management: Establish a feedback loop to automatically remove invalid or inactive email addresses.
- List Segmentation: Segment the list based on engagement to improve the relevance of emails and reduce unsubscribes.
- Compliance: Adhere to SMTP standards for proper email transmission and formatting.
- Monitoring Tools: Use appropriate monitoring tools to track sending reputation, bounce rates, and spam complaints.
- Error Code Analysis: Accurately interpret bounce error codes for rapid diagnosis and remediation of issues.
What email marketers say
13 marketer opinions
When encountering blocked bounces after the initial send with a new IP address, several key steps are essential to ensure email deliverability. Begin by investigating potential Proofpoint issues, especially for Apple domains and smaller domains, and check your IP against Proofpoint's lookup tool. Also, email icloudadmin@apple.com for assistance with Apple-related bounces. Ensure your content is free of spam triggers, third-party elements, or link shorteners, and verify your MX records. Monitor your sending reputation closely by tracking bounce rates, spam complaints, and engagement metrics, and segment your email list to initially target only your most engaged subscribers. Implement proper email authentication protocols (SPF, DKIM, DMARC) to verify sender identity and prevent spoofing. Gradually increase email volume to avoid triggering spam filters, and actively manage bounce rates by establishing a feedback loop to remove invalid addresses. Ensure your email content is of high quality, avoiding spam trigger words, excessive images, or misleading subject lines. Regularly clean your email list to remove inactive addresses and segment your list based on engagement to send targeted emails. Continuously monitor engagement metrics, such as open rates and click-through rates, to detect and address any deliverability issues promptly.
Key opinions
- Proofpoint Check: Blocked bounces could be related to Proofpoint. Check your IP and domains against Proofpoint.
- Apple Contact: For Apple-related bounces, contact icloudadmin@apple.com for assistance.
- Content Review: Ensure your email content is free of spam triggers, poor reputation elements, and link shorteners.
- Monitor Reputation: Closely monitor sending reputation, bounce rates, spam complaints, and engagement metrics.
- Engaged Subscribers: Initially send to your most engaged subscribers for better IP warming.
- Authentication Protocols: Implement SPF, DKIM, and DMARC for email authentication.
- Gradual Increase: Gradually increase email volume to avoid triggering spam filters.
- Bounce Management: Actively manage bounce rates and remove invalid addresses.
- Content Quality: Ensure high-quality email content, avoiding spam trigger words and misleading subject lines.
- List Cleaning: Regularly clean your email list to remove inactive or invalid addresses.
- Segmentation: Segment your list based on engagement and demographics for targeted emails.
- Engagement Monitoring: Continuously monitor engagement metrics such as open rates and click-through rates.
Key considerations
- Proofpoint Domains: Determine whether bounces are due to Proofpoint filtering, particularly for smaller domains or Apple-related addresses.
- Content reputation: Poor email content can cause the issue so clean your content before starting your campaign.
- List Quality: High bounce rates impact reputation and deliverability. Ensure list hygiene and engagement segmentation.
- Volume Ramping: Sudden spikes in sending volume can trigger spam filters. Implement a gradual warm-up schedule.
- Authentication Validity: Ensure SPF, DKIM, and DMARC records are properly configured to authenticate sending sources.
- Feedback Loops: Implement a feedback loop to receive and act on bounce and complaint notifications.
Marketer view
Email marketer from StackOverflow recommends thoroughly reviewing email content to ensure it does not contain spam triggers. Avoid using excessive exclamation points, spammy words, or broken links. Clean and relevant content helps improve deliverability.
18 May 2023 - StackOverflow
Marketer view
Marketer from Email Geeks advises that if the one-off domains are tied to Proofpoint, the issue needs to be addressed there. Also, suggests checking the content for anything with a poor reputation, like third-party elements or link shorteners and to check the MX record to see if they are using proofpoint.
26 May 2025 - Email Geeks
What the experts say
2 expert opinions
When facing blocked bounces after an initial send with a new IP, it's crucial to understand the specific error codes within the bounce messages, as they offer valuable insights into the underlying issues, such as spam filtering, recipient problems, or technical malfunctions. Additionally, proactively monitor and track your sending reputation, bounce rates, and spam complaints, using dedicated tools and processes to promptly identify and address deliverability issues.
Key opinions
- Bounce Message Analysis: Understanding bounce message error codes is critical for diagnosing delivery problems.
- Proactive Monitoring: Proactive monitoring of sending reputation, bounce rates, and spam complaints helps identify issues.
Key considerations
- Error Code Interpretation: Carefully interpret bounce message error codes to pinpoint the root cause of the delivery failures.
- Monitoring Tool Implementation: Set up tools and processes to continuously monitor sending reputation and identify deliverability problems.
Expert view
Expert from Spamresource.com responds that the most important step is to understand the bounce message, as the specific error codes provide crucial information for diagnosing and resolving the delivery issue. Different codes point to different problems, such as spam filtering, recipient issues, or technical errors.
14 Jul 2022 - Spamresource.com
Expert view
Expert from Word to the Wise shares that when you see blocked bounces, it's important to be proactive and set up comprehensive monitoring to identify deliverability issues. Use tools and processes to track your sending reputation, analyze bounce rates, and understand spam complaints, as these are key indicators to address and mitigate deliverability problems.
11 Jun 2022 - Word to the Wise
What the documentation says
4 technical articles
When dealing with blocked bounces on the first send with a new IP, it's vital to focus on several key areas. IP warming is crucial, involving a gradual increase in sending volume to build a positive reputation with ISPs. Adhering to email authentication standards like SPF, DKIM, and DMARC, and following email best practices, helps improve deliverability. Checking if the new IP is on any blocklists and requesting removal if necessary is also important. Finally, adhering to SMTP standards ensures proper email formatting and delivery, reducing the likelihood of bounces.
Key findings
- IP Warming: Gradually increase sending volume to build a positive reputation.
- Email Authentication: Adhere to SPF, DKIM, and DMARC standards for improved deliverability.
- Blocklist Check: Check if the new IP is on any blocklists and request removal.
- SMTP Standards: Adhere to SMTP standards for proper email transmission.
Key considerations
- Warming Schedule: Implement a structured IP warming schedule to gradually increase sending volume.
- Authentication Configuration: Properly configure SPF, DKIM, and DMARC records to authenticate your sending source.
- Blocklist Monitoring: Regularly check blocklist status and take necessary steps for removal.
- Compliance: Ensure compliance with SMTP standards for proper email transmission and formatting.
Technical article
Documentation from Mailjet explains that IP warming is crucial for new IPs. It involves gradually increasing sending volume to build a positive reputation with ISPs. Starting slow and increasing volume daily or weekly helps establish credibility and avoid being flagged as spam.
20 Apr 2025 - Mailjet
Technical article
Documentation from Microsoft recommends checking if the new IP address is on any blocklists. If the IP is blocklisted, take steps to request removal. Being blocklisted can significantly impact deliverability and cause bounces.
13 Sep 2022 - Microsoft
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