Summary
If Microsoft blocks your IP during IP warming, the consensus is to immediately cease sending to Microsoft domains and thoroughly investigate the root cause. This involves analyzing bounce messages (not relying solely on ESP classifications), checking blocklist status, and evaluating your sender reputation. Contact Microsoft support with comprehensive details about your sending practices, list acquisition methods, and adherence to their policies. Proactive measures are crucial, including requesting pre-emptive accommodation for new IPs, diligently managing your list quality by removing spam traps and unengaged users, and maintaining a strong sender reputation through proactive engagement monitoring and responsible sending habits. Finally, ensure your ESP contacts Microsoft for mitigation assistance.
Key findings
- Immediate Cessation of Sending: Immediately stop sending emails to Microsoft domains upon detection of a block to prevent further reputation damage.
- Thorough Investigation: Conduct a comprehensive investigation to identify the cause of the block, examining bounce messages, blocklists, and sender reputation.
- Direct Communication with Microsoft: Contact Microsoft support directly, providing detailed information about your sending practices and list acquisition.
- List Quality Management: Prioritize list quality by regularly removing spam traps, invalid addresses, and unengaged subscribers.
- Proactive Reputation Management: Actively manage and monitor your sender reputation through engagement monitoring, feedback loops, and adherence to best practices.
- Preemptive accommodation: Request Microsoft to perform pre-emptive accommodation, this can help prevent your block in the first place
Key considerations
- Compliance with Policies: Ensure strict compliance with Microsoft's email sending policies and guidelines.
- Review and Adjustment of Practices: Be prepared to review and adjust your email sending practices based on feedback from Microsoft and your own analysis.
- Engagement-Based Segmentation: Segment your email list based on engagement levels to improve deliverability and sender reputation.
- Full Rejection Message: ESP bounce classifications are often incorrect so ensure you get the full rejection message from Microsoft before contacting them.
- High Engagement: Its very important to maintain high engagement to avoid blocks, clean your list of old emails and unengaged users.
- ESP involvement: Ensure the Email Service Provider contacts Microsoft for mitigation assistance rather than you directly.
What email marketers say
11 marketer opinions
If Microsoft blocks your IP during IP warming, the immediate action is to stop sending to Microsoft domains and investigate the cause. This includes checking bounce messages, sender reputation, and list quality. Contact Microsoft support with details of your sending practices and be prepared to address any identified issues. Proactive measures, such as pre-emptive accommodation requests and managing IP reputation through engagement-based list segmentation, are also crucial.
Key opinions
- Immediate Stop: Immediately cease sending emails to Microsoft domains to avoid further damaging your reputation.
- Root Cause Analysis: Thoroughly investigate the reason for the block, including checking bounce messages, blocklists, and sender reputation using third-party tools.
- Contact Microsoft: Reach out to Microsoft support with detailed information about your sending practices, list acquisition methods, and compliance with their policies.
- List Quality: Assess and clean your email list, removing spam traps, invalid addresses, and unengaged subscribers to improve deliverability.
- Pre-emptive Accommodation: Before starting IP warming, submit a request for pre-emptive accommodation to Microsoft to inform them of your plans.
Key considerations
- Engagement Monitoring: Actively monitor engagement metrics and segment your list accordingly to ensure high engagement from recipients.
- Bounce Message Analysis: Carefully analyze bounce messages to understand the specific reasons for delivery failures and tailor your remediation efforts.
- Proactive Reputation Management: Proactively manage your IP reputation by monitoring feedback loops, handling unsubscribes promptly, and following email marketing best practices.
- Specific Bounce Resolution: If Microsoft shares a specific type of bounce e.g. S3140, S3150, or S775 then find specific fixes for this and provide it to microsoft.
- Third-Party reputation tools: Check sender reputation via third party tools to see if there are any blacklistings.
Marketer view
Email marketer from Quora states that if Microsoft blocks you during IP warming, you should verify the block isn't due to list contamination. She suggests running your email list through a cleaning service to remove spam traps and invalid addresses before contacting Microsoft support.
6 Feb 2023 - Quora
Marketer view
Email marketer from Litmus shares that it's important to identify deliverability problems, which is to check blocklists and bounce logs for specific error codes. Knowing the exact reason for the block helps you tailor your remediation steps when contacting Microsoft.
30 Jan 2022 - Litmus
What the experts say
4 expert opinions
If Microsoft blocks your IP address during IP warming, experts recommend stopping sending immediately. It's crucial to identify the cause by obtaining the real rejection message, reviewing blocklist status, and sender reputation. Contact Microsoft support with details about your sending practices, list acquisition, and compliance. Additionally, requesting pre-emptive accommodation for new IP addresses can help prevent blocks.
Key opinions
- Stop Sending Immediately: If blocked, halt sending to prevent further damage to your reputation.
- Get Real Rejection Message: Don't rely solely on ESP bounce classifications; obtain the actual rejection message for accurate troubleshooting.
- Identify the Cause: Review bounce messages, blocklist status, and sender reputation to determine the reason for the block.
- Contact Microsoft Support: Provide detailed information about your sending practices, list acquisition, and compliance with policies when contacting support.
- Pre-emptive Accommodation: Request pre-emptive accommodation for new IP addresses to inform providers like Microsoft about your warming plans.
Key considerations
- Adjust Sending Practices: Be prepared to adjust your sending practices based on feedback from Microsoft.
- Mitigation Help: ESPs should contact Microsoft for mitigation help and not just rely on the sender directly.
- Action on Bounces: Adjustments to fix the problem will be different based on the specific bounce messages you receive.
Expert view
Expert from Word to the Wise explains that if Microsoft blocks your IP address during warm-up, the first step is to stop sending mail immediately. Identify the cause by reviewing bounce messages, blocklist status, and sender reputation. Contact Microsoft support, providing detailed information about your sending practices, list acquisition, and compliance with their policies. Be prepared to adjust your sending practices based on their feedback.
27 Nov 2023 - Word to the Wise
Expert view
Expert from Spam Resource explains that you should request preemptive accommodation for new IP addresses. Some mailbox providers, like Microsoft, offer a process to register new IPs and inform them of your warming plans. Doing so can help avoid blocks during the initial phases of your warm-up.
27 Mar 2023 - Spam Resource
What the documentation says
4 technical articles
If your IP address is blocked during IP warming, documentation from multiple sources emphasizes the importance of pausing sending immediately. Review your sending practices, ensure compliance with policies (Microsoft's policies and Google's bulk sending guidelines), and investigate potential issues such as reputation problems, spam complaints, sending volume, and list quality. Contact the recipient domain's postmaster or support team, providing details about your sending practices and demonstrating adherence to best practices. Utilize tools like Microsoft's Sender Support form and Google's Postmaster Tools to identify and address deliverability issues.
Key findings
- Pause Sending: Immediately stop sending emails upon encountering a block.
- Review Sending Practices: Thoroughly examine your email sending practices for compliance with relevant guidelines.
- Address Reputation: Actively work to improve your IP's reputation, addressing issues such as spam complaints and list quality.
- Provide Details: Be prepared to provide detailed information about your sending practices to support teams.
- Utilize Tools: Make use of provided tools like Sender Support forms and Postmaster Tools to identify problems.
Key considerations
- Compliance: Ensure adherence to specific policies and guidelines of email providers like Microsoft and Google.
- Investigation: Thoroughly investigate the root causes of the block before resuming sending activities.
- Proactive Monitoring: Continuously monitor your IP's reputation and deliverability metrics to prevent future blocks.
- Adherence to Best Practices: Always adhere to well-established email marketing best practices, including permission-based sending and easy unsubscribe options.
Technical article
Documentation from Google explains to monitor your IP's reputation and ensure it remains high. If you are suddenly blocked, check compliance with bulk sending guidelines. Google recommends using their Postmaster Tools to identify any deliverability issues.
27 Feb 2022 - Google
Technical article
Documentation from SparkPost answers that if you get blocked, immediately pause sending, investigate the cause, and contact the recipient domain's postmaster or support team. Be prepared to provide details about your sending practices and demonstrate that you are following best practices.
26 Oct 2022 - SparkPost
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