Summary
Gmail rate limits Microsoft 365 emails due to a combination of factors: Gmail's protection mechanisms against spam, poor sending practices from the sender, and issues with authentication. Specific problems include missing or misconfigured DKIM records, reliance on SPF alone, sending high volumes of emails without proper warm-up, poor sender reputation, and inadequate list hygiene. To fix this, it's recommended to implement proper email authentication (SPF, DKIM, DMARC) with your own domain, warm up IP addresses, monitor sender reputation with tools like Google Postmaster Tools, segment and clean email lists, improve engagement metrics, avoid spam trigger words, and adhere to Gmail's and Microsoft's sending guidelines.
Key findings
- Gmail Protection: Gmail implements rate limits to protect users from spam and abuse, as a standard practice.
- Authentication Issues: Missing or misconfigured DKIM, or relying solely on SPF, leads to deliverability problems.
- Volume and Reputation: High email volume and a poor sender reputation significantly contribute to rate limiting.
- IP Warm-up Needed: Gradually warming up IP addresses builds a positive sending reputation.
- List Management: Poor list hygiene, including inactive or invalid addresses, harms sender reputation.
- Engagement Matters: Low engagement metrics negatively impact sender reputation.
Key considerations
- Implement DKIM: Configure DKIM with your own domain (not onmicrosoft.com) for email authentication.
- Authentication Protocols: Use SPF, DKIM, and DMARC for email authentication to verify sender identity.
- Monitor Reputation: Regularly check your sender reputation using Google Postmaster Tools or similar.
- Manage Lists: Segment email lists for targeted content and remove inactive subscribers.
- Review Guidelines: Adhere to Gmail's bulk sender guidelines to improve deliverability.
- Warm Up IP: Gradually increase sending volume when using a new IP address to avoid being flagged.
- Avoid Triggers: Avoid using spam trigger words in email content to minimize being marked as spam.
What email marketers say
11 marketer opinions
Gmail rate limits Microsoft 365 emails due to various factors including high email volume, poor sender reputation, and inadequate email authentication. To resolve this, it's crucial to properly authenticate emails using SPF, DKIM, and DMARC, warm up IP addresses gradually, monitor sender reputation through tools like Google Postmaster Tools, segment email lists for targeted content, clean email lists to remove inactive addresses, improve engagement metrics by providing valuable content, and avoid spam trigger words.
Key opinions
- Authentication: Proper email authentication (SPF, DKIM, DMARC) is essential for verifying sender identity and improving deliverability.
- Volume and Reputation: Sudden spikes in email volume and a poor sender reputation are major contributors to rate limiting.
- IP Warm-up: Gradually warming up IP addresses establishes a positive sending reputation with Gmail.
- List Hygiene: Cleaning email lists and removing inactive addresses prevents harm to sender reputation.
- Engagement Metrics: High engagement rates (opens, clicks) positively impact sender reputation and reduce rate limiting.
Key considerations
- Implement Authentication: Ensure SPF, DKIM, and DMARC are correctly configured for your domain to authenticate your emails.
- Monitor Reputation: Regularly monitor your sender reputation using tools like Google Postmaster Tools to identify and address deliverability issues.
- Segment Lists: Segment your email lists to send targeted content and improve engagement.
- Clean Lists: Remove inactive and invalid email addresses from your lists to maintain a healthy sender reputation.
- Avoid Spam Triggers: Refrain from using spam trigger words in your email subject lines and content.
Marketer view
Email marketer from Gmass recommends segmenting your email lists to send more targeted and relevant content to subscribers. This can improve engagement rates and reduce the likelihood of being marked as spam, which can lead to rate limiting.
13 May 2024 - Gmass Blog
Marketer view
Email marketer from Email Geeks reinforces that the issue is likely due to a high volume of problematic emails sent via Office 365 and recommends proper email authentication with the sender's own domain when sending through them.
6 Jul 2021 - Email Geeks
What the experts say
6 expert opinions
Gmail rate limits Microsoft 365 emails due to issues like missing or misconfigured DKIM, relying solely on SPF, poor sending practices, lack of list hygiene, and insufficient subscriber engagement. Solutions include implementing DKIM with your own domain, continuous IP and domain reputation monitoring, and effective subscriber engagement management.
Key opinions
- DKIM Importance: Missing or improperly implemented DKIM is a significant factor in Gmail rate limiting.
- SPF Reliance: Relying solely on SPF for authentication can contribute to deliverability issues.
- Poor Practices: Poor sending practices, such as high volume and lacking email authentication contribute to rate limiting.
- Reputation: Monitoring IP and domain reputation is crucial for identifying and addressing deliverability problems.
- Engagement: Managing subscriber engagement, including removing unengaged users, improves deliverability.
Key considerations
- Implement DKIM: Implement DKIM using your own domain, not the default onmicrosoft.com, to properly authenticate your emails.
- Monitor Reputation: Continuously monitor your IP and domain reputation for blacklisting and other issues.
- Manage Engagement: Actively manage subscriber engagement by removing unengaged subscribers and delivering valuable content.
- Authentication: Implement proper email authentication practices, including SPF, DKIM, and DMARC.
- List Hygiene: Practice good list hygiene by removing inactive or invalid email addresses.
Expert view
Expert from Spam Resource highlights the need for continuously monitoring your IP and domain reputation. Blacklisting can quickly lead to rate limiting issues, and proactive monitoring allows for swift corrective actions.
10 Jun 2024 - Spam Resource
Expert view
Expert from Email Geeks suggests that the Gmail rate limiting issue might be related to DKIM. Gmail might dislike the mail associated with the DKIM or SPF domain. Implementing DKIM as the sender's domain, not the default onmicrosoft.com domain, could help.
24 Apr 2024 - Email Geeks
What the documentation says
5 technical articles
Gmail rate limits Microsoft 365 emails to protect against spam and abuse, adhering to SMTP standards. These limits are based on sender reputation, email type, and various factors, with exceeding them resulting in temporary restrictions. Addressing this requires adherence to Microsoft's service limitations, implementing best practices, understanding Gmail's bulk sender guidelines, and utilizing DMARC for enhanced authentication and control over message handling.
Key findings
- Protection: Gmail implements rate limits to protect users from spam and abuse.
- Service Limits: Exceeding sending limits within Microsoft 365 can lead to rate limiting.
- SMTP Standards: SMTP rate limiting is a common practice for preventing abuse.
- DMARC Benefits: Implementing DMARC improves email deliverability and reduces rate limiting risk.
- Bulk Sender Guidelines: Following Gmail's bulk sender guidelines is essential for avoiding rate limits.
Key considerations
- Understand Limits: Review and adhere to sending limits within Microsoft 365.
- Implement DMARC: Implement DMARC to specify how email receivers should handle messages failing SPF and DKIM.
- Follow Guidelines: Adhere to Gmail's guidelines for bulk email senders, including authentication and list management.
- Best Practices: Implement best practices for sending email to external domains like Gmail.
- Review Practices: Regularly review your email sending practices to ensure they align with industry standards and Gmail's requirements.
Technical article
Documentation from RFC Editor explains SMTP rate limiting is a common practice to prevent abuse. SMTP servers often impose limits on the number of connections, messages, or recipients within a specific time frame. These limits are dynamically adjusted based on various factors.
17 Nov 2021 - RFC Editor
Technical article
Documentation from Google explains Gmail has specific guidelines for bulk email senders to ensure a positive user experience. Following these guidelines, including proper authentication, list management, and content quality, can help prevent rate limiting.
28 Jun 2024 - Google
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