What are spam filter clicks?

Spam filter clicks, often called bot clicks or automated clicks, are interactions generated by email service providers (ESPs) like Microsoft. These systems proactively scan emails for malicious content by opening links in a secure environment before the email reaches the recipient's inbox. This pre-screening activity registers as clicks in your email reports, even though a human recipient hasn't interacted with the email yet.

How can I tell if clicks are from spam filters or real users?

You can often identify these clicks by their unusual timing (occurring immediately after send), geographic origin (from data centers or unusual locations), or pattern (all links clicked simultaneously). While some ESPs offer features to filter these out, you might need to analyze your raw click data to differentiate them from genuine human engagement. You can also refer to why you're seeing bot clicks with Outlook.

Do spam filter clicks negatively affect my sender reputation?

These automated clicks are a security measure and do not directly harm your sender reputation. However, relying solely on inflated click rates for performance analysis can lead to misguided marketing decisions. The key is to understand why they occur and adjust your metrics to focus on real human engagement.

How can I ensure my emails still reach the inbox despite these clicks?

While you cannot stop spam filter clicks, you can ensure your deliverability to Hotmail and Outlook.com remains strong by: 1. Maintaining excellent sender reputation through consistent sending practices and content quality. 2. Ensuring all email authentication records (SPF, DKIM, DMARC) are correctly configured. 3. Avoiding blacklists (or blocklists) by regularly cleaning your email list and monitoring for spam trap hits. 4. Providing valuable content that encourages genuine user interaction.

Why does Microsoft perform these automated link scans?

Microsoft's systems, including Defender for Office 365 Safe Links , are designed to protect users from phishing and malware. They proactively scan email links in a sandboxed environment to assess their safety before delivery. This security measure is applied to both enterprise and consumer accounts (Hotmail, Outlook.com).

Why am I seeing spam filter clicks with Hotmail and Outlook.com? - Troubleshooting - Email deliverability - Knowledge base

For many email senders, a surge in clicks and opens from Hotmail and Outlook.com recipients can be puzzling, especially when these interactions appear almost immediately after an email is sent. It looks like an engagement spike, but often, it's not. This phenomenon has become increasingly common and is directly related to how major mailbox providers, particularly Microsoft, are evolving their security protocols.

I've spoken with numerous clients and colleagues who've observed this exact behavior. Emails sent to Microsoft consumer domains, including Hotmail and Outlook.com, sometimes show immediate, automated clicks and opens. This isn't necessarily a sign of malicious activity on your end, but rather an indicator of sophisticated anti-spam and anti-phishing measures at work.

These automated interactions can significantly skew your email marketing metrics, making it challenging to gauge true subscriber engagement. Understanding the underlying reasons for these artificial clicks and opens is crucial for any sender relying on accurate email performance data.

Understanding Microsoft's filtering mechanism

The primary reason for these unexpected clicks lies in the advanced security measures implemented by mailbox providers like Microsoft. Their systems are designed to proactively protect users from phishing attempts, malware, and other threats. This involves a process called URL scanning or link testing.

Before an email even reaches a user's inbox, Microsoft's filters (including Defender for Office 365 Safe Links) will open and click every link within the email in a sandboxed environment. This helps them determine if the links lead to malicious websites or contain harmful content. If a link is deemed unsafe, it can be rewritten, blocked, or the email might be moved to the junk folder or even rejected. This is also how automatic opens and clicks happen on Office 365 hosted recipient domains.

This behavior isn't new for enterprise-level Office 365 accounts, which often have advanced threat protection. However, a noticeable trend has emerged where this same proactive scanning is now more widely applied to free Hotmail and Outlook.com consumer accounts. This means even if you're not sending to corporate inboxes, you're likely to see these security-driven interactions.

How it works

Pre-delivery Scan: As soon as an email hits Microsoft's servers, automated systems analyze its content, including all embedded URLs.
Sandbox Environment: Links are opened in a secure, isolated environment to check for malware, phishing attempts, and other suspicious behavior, without risking the actual user.
Click Recording: The actions within this sandbox, including clicks on links, are recorded, which then register as clicks in your Email Service Provider (ESP) reports.

Identifying bot clicks versus genuine engagement

Distinguishing between a genuine click from a subscriber and an automated spam filter click can be challenging, but it's essential for accurate performance measurement. Automated clicks often exhibit specific patterns that can help you identify them.

Look for clicks that occur within seconds or minutes of the email being sent, especially from geographically diverse locations that don't match your target audience. These rapid-fire interactions are a strong indicator of automated bot activity rather than human engagement. While this behavior has been noted to increase overall click rates, it doesn't always translate to higher inbox placement.

Your ESP's reporting might show these as legitimate clicks, leading to inflated engagement metrics. It's important to cross-reference this data with other indicators, such as conversions, replies, or website traffic attributable to your email campaigns. For more insights on how these types of clicks impact your metrics, see why you're seeing inflated clicks.

Characteristic	Genuine Click	Spam Filter Click
Timing	Varied, often minutes to hours after send, reflecting recipient's active engagement.	Immediate, within seconds or very few minutes of the email being processed by Microsoft's servers.
IP Address / Location	Typically from the recipient's known or expected geographic region and IP range.	Often from data centers, cloud providers, or locations unrelated to your target audience.
Click Behavior	Clicks on specific links relevant to the recipient, often followed by further website activity.	All links in the email may be clicked, even unsubscribe links, in a consistent, programmatic manner.

Maintaining strong sender reputation

While automated clicks are a fact of life with modern email security, maintaining a strong sender reputation remains paramount for reaching the inbox. Microsoft's filters still heavily weigh reputation when deciding if an email lands in the inbox or the junk folder (or gets blocked entirely). Even if you experience automated clicks, poor sender reputation can lead to actual deliverability issues, meaning your emails won't even make it past the initial filters.

Ensuring your email authentication protocols, such as SPF, DKIM, and DMARC, are correctly configured is the first step. These protocols prove to mailbox providers that you are who you say you are, significantly boosting your trustworthiness. You can check your email deliverability for free using an email deliverability tester.

Beyond authentication, focus on maintaining a clean email list by regularly removing inactive or invalid addresses. Consistent engagement from your genuine subscribers, low spam complaint rates, and avoiding email blocklists (or blacklists) are critical factors that contribute to a healthy sender reputation, regardless of automated click behavior.

Strategies for accurate reporting and analysis

Since these filter clicks are here to stay, adjusting how you analyze your email campaign performance is important. Simply relying on total click rates from your ESP might give you a misleading picture of your audience's true engagement.

Instead, consider these strategies:

Filter out bot clicks: Implement methods to identify and exclude known bot activity from your reports. Some ESPs offer this functionality, or you might need to analyze raw log data to filter out clicks originating from data center IPs or specific user agents.
Focus on deeper metrics: Pay more attention to metrics like conversions, website visits, time on site, or direct replies. These indicators are less susceptible to automated interference and provide a more accurate picture of engagement.
Segment your data: Analyze Hotmail and Outlook.com performance separately. This can help you understand their specific patterns and compare them against other domains.
Leverage Microsoft's tools: While not directly for filtering clicks, familiarize yourself with Microsoft's Sender Support options and their postmaster services to gain insights into your sending reputation with them. This is similar to how Google Postmaster Tools operates for Gmail.

Views from the trenches

Best practices

Always prioritize email authentication (SPF, DKIM, DMARC) to build and maintain strong sender trust with Hotmail and Outlook.com.

Regularly clean your email lists to remove inactive or invalid addresses, which reduces bounces and spam trap hits, safeguarding your reputation.

Focus on delivering valuable, relevant content that encourages genuine engagement and minimizes spam complaints, improving your sender score.

Analyze engagement metrics beyond raw clicks, such as conversions and website behavior, to accurately assess campaign performance and ROI.

Utilize Microsoft's sender tools and postmaster insights to proactively monitor your deliverability and address potential issues.

Common pitfalls

Over-relying on reported click rates from your Email Service Provider (ESP) without accounting for automated spam filter clicks, leading to misinterpretations.

Ignoring Microsoft's sender guidelines and best practices, which can result in increased filtering to the junk folder or even email blocking.

Sending to unengaged or old email addresses, which can lead to spam complaints, blocklistings (or blacklistings), and a decline in sender reputation.

Neglecting to monitor your sender reputation proactively, missing early warning signs of deliverability issues with Hotmail and Outlook.com.

Failing to segment your Hotmail/Outlook.com recipients, which prevents tailored analysis and specific optimization strategies for those domains.

Expert tips

Implement a robust DMARC policy (even p=none initially) to gain visibility into your email authentication results and identify unauthorized sending.

Use bounce reports from your ESP to pinpoint and remove invalid email addresses efficiently, preserving your list hygiene and sender score.

A/B test different subject lines and email content to determine what truly resonates with your audience and drives authentic clicks and conversions.

Keep an eye on trends in your click-to-open rates for Hotmail and Outlook.com to differentiate between normal security scanning and actual engagement dips.

Regularly review your email content for anything that might trigger spam filters, such as excessive images, short links, or promotional language.

Expert view

Expert from Email Geeks says this behavior has been reported from different companies since last November. Microsoft appears to be testing something and picking ESPs or senders to follow all the links on.

2024-07-18 - Email Geeks

Marketer view

Marketer from Email Geeks says many people are seeing a lot of non-human interaction from Microsoft recipients. They seem to be targeting chunks of network space, apparently randomly, which suggests testing.

2024-07-18 - Email Geeks

Key takeaways

The increase in spam filter clicks from Hotmail and Outlook.com is a clear sign of the evolving landscape of email security. While it can complicate your reporting, it's a necessary measure taken by mailbox providers to protect their users from sophisticated threats.

By understanding that these clicks are largely automated and by adjusting your analytical approach, you can still gain valuable insights into your email program's true performance. It's not about eliminating these clicks, but about accurately interpreting them.

Ultimately, your focus should remain on delivering high-quality, relevant content to an engaged audience, while ensuring your email infrastructure adheres to all technical best practices. This approach will ensure maximum deliverability, even with the presence of proactive spam filter scanning.

If you're noticing a significant uptick in bot clicks or other deliverability issues, particularly with Microsoft, it's worth reviewing your entire email program to identify any underlying issues that could be impacting your sender reputation. For more on this, consider why emails are suddenly going to spam with Outlook and Hotmail.