Emails are likely being filtered as spam by Hotmail due to a combination of factors involving sender reputation, email authentication, content, list management, and Microsoft's specific filtering policies. A low sender reputation, influenced by high bounce and complaint rates, can lead to emails being flagged as spam. Failing to properly authenticate emails using SPF, DKIM, and DMARC also contributes to deliverability issues. Content that includes spam trigger words, high image-to-text ratios, or is not personalized can trigger spam filters. Poor list management practices, such as not using double opt-in and making unsubscribing difficult, increase the likelihood of spam complaints. Finally, Microsoft's specific filtering criteria, including their SmartScreen filter and potentially limited responsiveness to sender feedback, necessitate careful adherence to best practices and monitoring of deliverability metrics. It's also worth noting that Microsoft appears to have migrated from Hotmail to Outlook Protection impacting email filtering.
14 marketer opinions
Emails are likely going to the spam box in Hotmail (Outlook) due to a combination of factors related to sender reputation, email content, authentication, and user engagement. Microsoft uses sophisticated filtering systems that evaluate sender reputation based on metrics like bounce rates, complaint rates, and engagement. Poor reputation, being blacklisted, or failing to authenticate emails properly (SPF, DKIM, DMARC) can result in spam placement. Content issues, such as using spam trigger words, high image-to-text ratios, and lack of personalization, can also trigger filters. Additionally, not adhering to best practices for list management, such as using double opt-in and providing easy unsubscribe options, contributes to deliverability problems. Engaging with Microsoft's mitigation form and actively monitoring and improving sender reputation are crucial.
Marketer view
Email marketer from Webmaster Forum suggests segmenting your email list to send more targeted and relevant content to subscribers. Sending the same email to everyone can increase spam complaints and negatively affect your sender reputation with Hotmail.
27 Sep 2021 - Webmaster Forum
Marketer view
Email marketer from Email Geeks shares that if you're being put in the spam folder, your best bet is to fill out the mitigation form and make your case.
10 Aug 2022 - Email Geeks
6 expert opinions
Experts suggest that Hotmail/Outlook's spam filtering is influenced by several factors including sender reputation, email content, and user feedback. Microsoft's SmartScreen filter analyzes these signals to determine whether an email should be placed in the inbox or spam folder. Maintaining a good sender reputation by monitoring bounce rates, complaint rates, and engagement metrics is crucial. Additionally, it's important to ensure your IP or domain is not on any blocklists. Microsoft often prioritizes its own filtering preferences over sender feedback, making it essential to adhere to their guidelines.
Expert view
Expert from Spam Resource explains that Microsoft's SmartScreen filter analyzes various signals, including sender reputation, content, and user complaints, to filter spam. They suggest that senders focus on building a good reputation by sending wanted mail and avoiding spam traps.
13 Mar 2022 - Spam Resource
Expert view
Expert from Spam Resource explains that Microsoft (Hotmail/Outlook) uses a combination of reputation, content, and user feedback to determine if an email should be placed in the inbox or spam folder. They advise checking your sender reputation and ensuring that your email content is not triggering spam filters.
29 Nov 2023 - Spam Resource
5 technical articles
Documentation emphasizes the importance of adhering to email best practices and standards to ensure deliverability to Hotmail. Strict policies regarding spam and unsolicited email require senders to focus on email authentication (SPF, DKIM, DMARC), proper list management, and content creation. Correctly formatted emails following IETF standards, along with robust authentication methods, help prevent spoofing and improve deliverability. Monitoring DMARC reports aids in identifying and addressing any authentication failures.
Technical article
Documentation from DKIM explains that DomainKeys Identified Mail (DKIM) provides an email authentication system that allows email senders to digitally sign their messages, which email receivers can then verify. Implementing DKIM can significantly improve email deliverability to Hotmail by proving email authenticity.
18 Jul 2021 - DKIM
Technical article
Documentation from DMARC.org explains that Domain-based Message Authentication, Reporting & Conformance (DMARC) builds upon SPF and DKIM to provide a policy that tells email receivers what to do with emails that fail authentication checks. Implementing DMARC and monitoring reports can help identify and address spoofing attempts, improving deliverability to Hotmail.
26 Nov 2021 - DMARC.org
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