Summary
Many email marketers and deliverability professionals observe what appear to be automatic opens and clicks on emails sent to Office 365 hosted recipient domains. This phenomenon often leads to confusion regarding campaign performance and subscriber engagement. The primary driver behind these automated interactions is typically Microsoft's robust security features, particularly Microsoft Defender for Office 365's Safe Links and Safe Attachments policies. These systems are designed to pre-scan emails for malicious content, including URLs and attachments, by simulating user interaction. While beneficial for security, this pre-scanning can inadvertently trigger tracking pixels (opens) and even click on links (including unsubscribe links) before the actual recipient has viewed the email.
Key findings
- Security Pre-scanning: Office 365 utilizes features like Safe Links and Safe Attachments within Microsoft Defender to proactively scan email content for threats. This involves a sandboxed environment opening emails and clicking links to analyze their safety.
- Impact on Metrics: These automated interactions inflate open rates and click-through rates, making it challenging for senders to gauge genuine subscriber engagement. It's crucial to identify and filter out such artificial engagement.
- Unsubscribe Link Clicks: A notable consequence is that Safe Links can click unsubscribe links, potentially leading to unintended unsubscribes or false positives in subscriber churn data.
- IP Addresses: Automated opens and clicks typically originate from Microsoft's own IP ranges, which can often be identified through email tracking logs, distinguishing them from recipient engagement.
Key considerations
- Metric Adjustment: Email marketers should adjust their expectations for open and click metrics, particularly for audiences heavy on Office 365 domains. Focus on more reliable engagement indicators, such as conversions or replies.
- Segment Analysis: Segment your audience by domain to gain clearer insights into engagement patterns. This helps in understanding how Office 365's filtering affects your deliverability.
- Link Tracking: Be aware that any link within your email, including internal navigation or social media links, can be clicked by these automated systems.
- Email Authentication: Ensure your email authentication protocols like SPF, DKIM, and DMARC are correctly configured. Strong authentication can improve trust with Office 365 and potentially influence how aggressively emails are scanned. You can learn more about a simple guide to DMARC, SPF, and DKIM.
What email marketers say
Email marketers frequently express concern over misleading engagement metrics resulting from automated opens and clicks on Office 365 recipient domains. They often seek clarification on whether others are experiencing similar issues and how to accurately interpret their campaign data. The primary impact noted is the skewing of open and click rates, making it difficult to assess true subscriber interest and campaign effectiveness. There's also a significant point of concern around automated clicks on unsubscribe links, which can artificially inflate unsubscribe rates or lead to unexpected list churn.
Key opinions
- Skewed Metrics: Many marketers report inflated open and click rates, making campaign performance analysis difficult. This leads to a need for alternative methods to measure engagement beyond traditional tracking pixels.
- Unsubscribe Risk: A key worry is the automated clicking of unsubscribe links by security scanners, potentially leading to genuine subscribers being removed from lists without their intent.
- Security vs. Data Accuracy: Marketers recognize the security benefits of Microsoft's features but lament the trade-off in reliable data. They often wish for better ways to distinguish human interaction from bot activity. Our guide on identifying automated scripts might be helpful.
- Identifying Source: The consensus is that these automated interactions are primarily from Microsoft Defender for Office 365, indicating it's a systemic behavior across Office 365 environments.
Key considerations
- Focus on Conversion: Shift focus from vanity metrics like opens to hard conversions, purchases, or other bottom-of-funnel actions that directly impact business goals. Consider the impact on click-through rates.
- Audience Segmentation: Segment lists by recipient domain to better understand where automated activity is most prevalent. This allows for more targeted analysis and potentially different measurement strategies for Office 365 domains.
- URL Rewriting: Understand that Office 365 Safe Links often rewrite URLs, which can sometimes interfere with specific tracking mechanisms or lead to unexpected redirects.
- Clear Communication: Communicate these observed phenomena to stakeholders, explaining why traditional email metrics may not be entirely accurate for Office 365 recipients. This also impacts why O365 may mark emails as spam from third-party ESPs.
Marketer view
Email marketer from Email Geeks notes a pattern of automatic opens and clicks originating from Office 365 hosted recipient domains. This observation highlights a common issue where email campaign engagement metrics appear inflated due to automated security scans rather than genuine user interaction. They are seeking confirmation from other senders if they are experiencing similar discrepancies in their reporting, suggesting that this is a widespread challenge in accurately assessing email performance when targeting Office 365 users.
Marketer view
Email marketer from Email Geeks confirms that Microsoft Defender is indeed clicking on all links, including unsubscribe links, causing significant issues for their email programs. This behavior directly impacts the accuracy of unsubscribe metrics, potentially leading to unintended subscriber loss or misinterpretations of list health. This unsolicited interaction by automated systems means that a click on an unsubscribe link cannot be definitively attributed to a user's desire to opt out, complicating list management and compliance efforts.
What the experts say
Deliverability experts consistently identify Microsoft Defender for Office 365's Safe Links and Safe Attachments as the primary cause of artificial opens and clicks. They emphasize that this behavior is a security feature, not an indication of a problem with the sender's email program (unless the email is genuinely malicious). Experts advise senders to understand the technical mechanisms behind these interactions and to adjust their reporting methodologies accordingly. A key takeaway is that these automated scans are a defensive measure to protect end-users from phishing and malware, even if they introduce complexities for email marketers.
Key opinions
- Security Intent: The core reason for these interactions is Microsoft's commitment to security, pre-scanning content in a safe environment to detect threats before they reach the inbox. This proactive defense is critical for mitigating phishing and malware attacks.
- Standard Behavior: Automated opens and clicks are considered standard operating procedure for many modern mailbox providers, especially those with advanced threat protection, like Microsoft. It's not unique to Office 365, though Microsoft's implementation is particularly noticeable.
- Data Interpretation: Experts stress that traditional open and click metrics are no longer entirely reliable indicators of human engagement for all recipients. Senders must evolve their data analysis to account for bot activity. This ties into understanding why deliverability rates might be wrong.
- Impact on Deliverability: While these clicks don't necessarily harm deliverability, a sudden spike in opens or clicks from unusual IPs could sometimes be a sign that emails are being routed through certain security layers before reaching the inbox.
Key considerations
- IP Filtering: Analyze tracking data to identify and filter out opens and clicks from known Microsoft IP ranges (or those of other security vendors) to get a clearer picture of human engagement.
- Alternative Metrics: Emphasize unique clicks (after initial bot activity), replies, forwards, and conversions as more reliable indicators of engagement for Office 365 recipients. This aligns with modern technical solutions for deliverability.
- Unsubscribe Management: Implement double opt-out confirmations for unsubscribe links if automated clicks cause significant issues, ensuring that only genuinely opted-out users are removed from lists.
- Email Header Analysis: Examine email headers for clues from Microsoft's Exchange Online Protection (EOP) or Defender for Office 365, as these can indicate whether an email has passed through their scanning systems. This can help diagnose DMARC issues in Microsoft 365.
Expert view
Email expert from Spam Resource discusses the challenge of distinguishing between legitimate and automated engagement. They emphasize that while security features like Safe Links are necessary, they complicate the interpretation of traditional email metrics. Senders must adapt their analytical approaches to account for this prevalent bot activity, focusing on downstream conversions rather than just open and click rates.
Expert view
Deliverability expert from Word to the Wise explains that automated clicks on unsubscribe links are a side effect of aggressive security scanning, not necessarily a sign of malicious intent from the scanner. They point out that these systems are designed to test all URLs for safety, and an unsubscribe link is just another URL. This behavior underscores the need for senders to implement robust unsubscribe processes that handle such automated requests gracefully, preventing unintended removals.
What the documentation says
Official Microsoft documentation and security advisories confirm that Microsoft Defender for Office 365 (formerly ATP) actively employs features like Safe Links and Safe Attachments. These features are designed to protect users from phishing, malware, and other threats by performing real-time, sandboxed analysis of email content. This analysis includes detonation of URLs and attachments, which inherently triggers tracking pixels and clicks on links within the email environment before it reaches the end-user's inbox. The documentation outlines the configurable policies for these features, including options for exclusions, but emphasizes their role in maintaining a secure email ecosystem.
Key findings
- Safe Links Functionality: Microsoft's Safe Links feature rewrites URLs in emails and then scans them at the time of click. However, it also performs initial pre-scan checks that can result in automated clicks as part of its threat detection process.
- Safe Attachments Behavior: The Safe Attachments feature uses a virtual environment (detonation chamber) to open and test attachments, which can also trigger embedded tracking pixels or external calls if the attachment content involves such elements.
- Policy Configuration: Administrators can configure Safe Links policies within the Microsoft 365 Defender portal, allowing for exclusions of specific URLs or domains from being rewritten or scanned. This offers some control over automated interactions, although not at the level of specific link types (e.g., unsubscribe).
- Protection Priority: The documentation consistently emphasizes that these features prioritize user protection from advanced threats, accepting that some automated interactions are a necessary byproduct of comprehensive security scanning.
Key considerations
- Admin Control: While automated opens and clicks are largely unavoidable, Office 365 administrators have some control through Safe Links policies to exclude trusted domains from certain scanning behaviors. This configuration is critical for managing whitelisting domains in Office 365.
- Email Header Information: Microsoft Exchange Online Protection (EOP) and Defender for Office 365 add specific headers to emails that indicate the scanning and verdict status. Analyzing these headers can provide insights into how an email was processed.
- Evolving Threats: Microsoft continually updates its threat protection mechanisms, meaning the exact behavior of Safe Links and Safe Attachments may evolve over time in response to new attack vectors. Staying informed about these updates is key. Learn more about Office 365 Advanced Threat Protection.
- User Awareness: The documentation often highlights the importance of user awareness and training alongside technical controls to enhance overall security posture. This reduces reliance solely on automated scanning to catch all threats.
Technical article
Microsoft Learn documentation for Safe Links explains how this feature is designed to protect users from malicious URLs in emails. It details that Safe Links analyzes links by rewriting them and then performing a reputation check at the time of click. This process may involve pre-scanning, which can result in automated 'clicks' as the system verifies the safety of the destination URL. The core purpose is to prevent users from accidentally navigating to harmful websites, prioritizing security over perfect tracking accuracy.
Technical article
Practical 365 documentation discusses how third-party mail filtering integrates with Office 365 and the methods attackers use to bypass these systems. It highlights that if not properly secured, malicious content can be delivered directly to Office 365 without passing through the intended filtering gateway. This emphasizes the critical role of Office 365's native security features, like Safe Links, in catching threats that might otherwise slip through, even if it leads to automated interactions.
Related resources
6 resources
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