Summary
Mimecast and Proofpoint employ multi-layered scrutiny involving reputation checks (IP, domain, sender), content and behavioral analysis, and real-time blacklists like Spamhaus. Mimecast's filtering is notably aggressive, with potential problems for shared IPs via Spamcop. Improving inbox placement beyond whitelisting necessitates a holistic approach. Essential elements include proper implementation and continuous monitoring of SPF, DKIM, and DMARC for authentication; maintaining a clean IP and domain reputation; practicing excellent list hygiene by removing inactive addresses; personalizing and segmenting email content for increased relevance and engagement; ensuring emails render correctly across all devices; and avoiding spam trigger words. Consistent sending volumes and proactive list management are also vital, along with warming up new dedicated IPs.
Key findings
- Reputation Matters: Mimecast and Proofpoint heavily rely on sender reputation (IP, domain) to filter emails, with Mimecast using Spamcop, which can impact shared IPs.
- Authentication is Crucial: Correct setup and monitoring of SPF, DKIM, and DMARC are paramount for authenticating sender identity and ensuring email integrity.
- Content Analysis: Both platforms analyze email content, making it crucial to avoid spam trigger words and create engaging, relevant material.
- List Hygiene Impacts Delivery: Regularly cleaning email lists to remove inactive or invalid addresses is critical for maintaining a good sender reputation.
- Engagement Drives Placement: Segmentation, personalization, and proper email rendering enhance engagement and reduce the likelihood of being marked as spam.
- Blacklists are Important: Mimecast and Proofpoint utilise real-time blacklists like Spamhaus to identify and block spammers. Ensure your IP address is not listed on any major RBLs.
- Proactive is better: Employ sophisticated content analysis, behavioral analysis, and reputation checks to identify and filter unwanted email. Beyond whitelisting, consistent email volume, relevant content, and proactive list management are crucial for inbox placement.
Key considerations
- Shared vs Dedicated IP: Carefully evaluate the impact of shared IPs and consider migrating to a dedicated IP for better control over reputation.
- Ongoing Authentication Management: Regularly review and update SPF, DKIM, and DMARC records to stay ahead of evolving security standards and prevent authentication failures.
- Content Quality Control: Implement rigorous content checks to avoid spam trigger words and ensure emails provide value to recipients.
- Continuous List Maintenance: Establish a process for regularly cleaning and segmenting email lists to maximize engagement and minimize bounces and spam complaints.
- Email Rendering Tests: Test email rendering across various clients and devices to ensure a consistent user experience and prevent display issues that could trigger spam filters.
- Warming: Remember to allow a warm-up period for new IP addresses
What email marketers say
7 marketer opinions
Email marketers suggest that improving inbox placement with Mimecast and Proofpoint, beyond whitelisting, involves a multi-faceted approach focused on sender reputation and email engagement. Key areas include warming up IP addresses, maintaining consistent sending volumes, practicing good list hygiene by removing inactive subscribers, segmenting email lists for more targeted messaging, personalizing email content, ensuring proper rendering across devices, avoiding spam trigger words, A/B testing for optimization, and monitoring bounce rates and spam complaints.
Key opinions
- IP Warm-up & Volume: Gradually warming up IP addresses and maintaining consistent sending volumes are crucial for establishing a positive sender reputation.
- List Hygiene: Regularly cleaning email lists to remove inactive or invalid addresses significantly improves deliverability.
- Segmentation & Personalization: Segmenting lists and personalizing content increases engagement and reduces the likelihood of being marked as spam.
- Content Quality: Engaging, relevant content that avoids spam trigger words is essential for successful inbox placement.
- Email Rendering: Ensuring emails render correctly across different devices and email clients reduces spam complaints.
- A/B Testing: Using A/B testing helps optimize email strategy and improve engagement, positively impacting sender reputation.
- Monitoring: Closely monitoring bounce rates and spam complaints is essential for identifying and addressing deliverability issues.
Key considerations
- Sender Reputation: Prioritize building and maintaining a positive sender reputation as it's a primary factor in how Mimecast and Proofpoint filter emails.
- Engagement Metrics: Focus on improving email engagement metrics (open rates, click-through rates) as these signals indicate the value of your emails to recipients.
- Proactive Approach: Implement a proactive email marketing strategy that emphasizes list hygiene, relevant content, and ongoing optimization to stay ahead of evolving filtering techniques.
- Authentication protocols: Make sure authentication is setup correctly (SPF, DKIM, DMARC).
Marketer view
Email marketer from Woodpecker.co shares that personalizing your email content can help improve engagement and reduce the likelihood of being flagged as spam. Mimecast and Proofpoint are more likely to view personalized emails as legitimate communication.
21 Apr 2022 - Woodpecker.co
Marketer view
Email marketer from SendGrid explains that segmenting your email lists based on subscriber behavior and demographics allows you to send more targeted and relevant emails. This can improve engagement and reduce spam complaints, ultimately benefiting your sender reputation with Mimecast and Proofpoint.
9 Mar 2022 - SendGrid
What the experts say
5 expert opinions
Experts indicate that Mimecast and Proofpoint employ various methods to scrutinize senders, including leveraging Spamcop for IP reputation (which is problematic for shared IPs), analyzing content, observing sender behavior, and conducting general reputation checks. Mimecast's filtering is notably aggressive. Recommendations for improved inbox placement, beyond whitelisting, involve ensuring proper email authentication (SPF, DKIM, DMARC), maintaining a clean IP address and sender reputation, avoiding spam trigger words, maintaining consistent email volume, providing relevant content, and practicing proactive list management. The timing for warming up a new dedicated IP address varies.
Key opinions
- Mimecast & Spamcop: Mimecast uses Spamcop, which can cause deliverability issues, especially for senders on shared IPs.
- Proofpoint & IP Rep: While not explicitly confirmed, it's highly likely that Proofpoint considers IP reputation in its filtering processes.
- Authentication is Key: Proper implementation of SPF, DKIM, and DMARC is crucial for proving sender legitimacy to both Mimecast and Proofpoint.
- Clean IP Essential: Maintaining a clean IP address, free from spam listings, is critical for bypassing filters.
- Content Matters: The content of emails is analyzed, and avoiding spam trigger words is important.
- Holistic Approach: Consistent email volume, relevant content, and proactive list management contribute to a positive sender reputation and improved inbox placement.
- Warm-up Considerations: When moving to a dedicated IP, the warm-up period can vary depending on specific details, and immediate warm-up isn't always guaranteed to be safe.
Key considerations
- Dedicated vs. Shared IP: Assess the impact of shared IPs on deliverability and consider transitioning to a dedicated IP if necessary.
- Authentication Protocols: Implement and regularly audit SPF, DKIM, and DMARC configurations to ensure they are accurate and effective.
- Content Strategy: Develop a content strategy that focuses on delivering relevant, engaging content to subscribers, avoiding spam-like characteristics.
- Proactive Monitoring: Continuously monitor IP and domain reputation, bounce rates, and spam complaints to identify and address deliverability issues promptly.
- Aggressive filtering: Be aware of Mimecast's aggressive filtering, and review wordtothewise's recommendations.
Expert view
Expert from Email Geeks explains that if moving traffic to dedicated IPs and a dedicated subdomain, the time to hold off sending before starting warm-up depends on the details, but it's probably fine to start warm-up immediately, though it's not a guarantee.
25 Apr 2025 - Email Geeks
Expert view
Expert from Email Geeks shares she isn’t sure about Proofpoint, but wouldn’t be shocked to learn they still look at IP reputation.
12 Oct 2024 - Email Geeks
What the documentation says
6 technical articles
Email deliverability, particularly when dealing with Mimecast and Proofpoint, hinges on establishing a strong sender reputation and implementing robust authentication protocols. These platforms scrutinize senders using IP, domain, and sender reputation checks, often leveraging real-time blacklists like Spamhaus to identify and block malicious actors. Key to improving inbox placement is ensuring proper configuration of SPF, DKIM, and DMARC, which not only verify sender identity but also specify how receivers should handle emails failing authentication. Maintaining a clean IP reputation is also critical.
Key findings
- Reputation Checks: Mimecast utilizes comprehensive reputation checks encompassing IP, domain, and sender reputation to identify and block malicious emails.
- Authentication Protocols: Proofpoint places significant emphasis on SPF, DKIM, and DMARC for verifying sender identity and improving inbox placement.
- Real-time Blacklists: Both Mimecast and Proofpoint utilize real-time blacklists like Spamhaus to identify and block senders with poor reputations.
- SPF Importance: Proper configuration of SPF records is essential for specifying authorized mail servers and preventing spoofing.
- DKIM Implementation: Implementing DKIM allows for digitally signing emails, verifying that the email hasn't been tampered with.
- DMARC Policy: Implementing DMARC helps specify how receivers should handle emails that fail SPF and DKIM checks, boosting domain reputation.
Key considerations
- Sender Reputation Management: Proactively monitor and manage IP, domain, and sender reputation to prevent being flagged as a malicious sender.
- Authentication Configuration: Ensure SPF, DKIM, and DMARC records are accurately configured and regularly reviewed to adapt to evolving email security standards.
- Blacklist Monitoring: Continuously monitor IP addresses against major real-time blacklists to promptly address any listings.
- Policy Enforcement: Implement and enforce strong DMARC policies to protect your domain from email spoofing and phishing attacks.
Technical article
Documentation from Spamhaus explains that Maintaining a clean IP reputation is essential. Mimecast and Proofpoint both utilize real-time blacklists (RBLs) like Spamhaus to identify and block spammers. Ensure your IP address is not listed on any major RBLs.
26 May 2024 - Spamhaus
Technical article
Documentation from DKIM.org explains how to implement DKIM (DomainKeys Identified Mail) to digitally sign your emails. This cryptographic signature verifies that the email was sent by an authorized sender and has not been tampered with, enhancing your credibility with Mimecast and Proofpoint.
18 Feb 2024 - DKIM.org
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