Why are we seeing transactional deliverability issues on Microsoft even though SNDS seems to be showing up green?

Email marketer from StackOverflow explains that If using shared IP addresses, a sudden spike in bounce rates and spam complaints from other senders on the same IP can affect your deliverability to Microsoft, regardless of your own SNDS standing. Recommend monitoring shared IP reputation closely.

Email marketer from Email Vendor Guide explains that Microsoft uses its own internal reputation systems separate from SNDS. Even with a good SNDS reputation, internal factors can impact deliverability to Office 365 users. They recommend proactively managing your sending reputation specifically with Microsoft through their feedback loops and reporting mechanisms.

Email marketer from Warmup Inbox explains that new IP addresses require a proper warm-up strategy, even if SNDS initially shows a good standing. Sudden large-volume sending from a new IP to Microsoft can trigger filtering.

Email marketer from Email on Acid shares that spam triggers in email content can cause deliverability problems with Microsoft. Elements like excessive use of spam trigger words, poor HTML coding, and missing text-to-HTML ratio can cause issues, even with a clean SNDS report.

Email marketer from Litmus explains that poor list hygiene, leading to high bounce rates and spam complaints, affects deliverability to Microsoft domains. Cleaning your list regularly helps mitigate the issue, even if SNDS shows no problems.

Email marketer from GMass shares that Microsoft may throttle email volume from senders who suddenly increase their sending rate, irrespective of their SNDS status. Gradual ramping up of volume is recommended.

Email marketer from Reddit shares that Office 365's filtering is heavily user-driven. If users frequently mark emails from a sender as spam, deliverability suffers, regardless of SNDS status. They suggest focusing on engagement metrics to improve deliverability to O365.

Email marketer from Mailjet shares that maintaining good IP reputation with Microsoft involves proactively monitoring bounce rates and spam complaints, as well as ensuring proper authentication (SPF, DKIM, DMARC). They emphasize that Microsoft heavily weighs user feedback.

Email marketer from Sender Score shares that various other reputation services exist. Your reputation on these can influence Microsoft’s filtering decisions. It's essential to monitor your reputation across multiple platforms, not just SNDS.

Expert from Spam Resource explains that Microsoft's filtering systems are complex and use a variety of signals, including user complaints, content analysis, and sender reputation data beyond what is shown in SNDS. A green SNDS status does not override negative signals from these other systems.

Expert from Email Geeks explains if the issue keeps happening, there is likely a problem in the address acquisition process, and emphasizes that users on O365 can easily mark emails as spam. This impacts reputation at Microsoft, but this information is not available through SNDS or JMRP messages, requiring different reputation management strategies than consumer domains.

Expert from Word to the Wise responds that Microsoft’s deliverability issues can often stem from aggressive filtering due to user-generated spam reports. She explains a green SNDS score doesn't account for individual user spam complaints. Focusing on opt-in processes and content is crucial.

Expert from Email Geeks asks about data sanitization being done at the collection point, after the person mentioned they saw a jump in bounces when migrating to Iterable. The person confirmed these were all new contacts and not carried over bounces.

Expert from Email Geeks explains that SNDS data is not from O365 accounts and is not useful for Office365 transactional deliverability issues. She asks if the IP has been delisted.

Documentation from Microsoft explains that end-user spam reporting (clicking 'This is Spam' in Outlook) is a strong signal for Microsoft's filtering systems. Even with a green SNDS status, a high rate of spam reports will negatively impact deliverability.

Documentation from Microsoft explains that a common reason for transactional email deliverability issues to O365 is being placed on a blocked sender list, either by individual users or by Microsoft's automated systems. These lists are separate from SNDS data.

Documentation from RFC explains that Ensuring proper SMTP standards compliance (RFC 5321, etc.) can avoid deliverability issues with Microsoft. Non-compliant emails are often flagged, even if SNDS is green.

Documentation from DMARC.org explains that strict DMARC policies (especially 'reject') enforced by recipient domains (including those hosted on O365) can block emails failing authentication checks. Even if your SNDS status is green, failing DMARC can cause deliverability issues to those domains.

Documentation from Microsoft explains that SNDS (Smart Network Data Services) primarily reflects data related to Outlook.com and not necessarily all aspects of Microsoft's email services, including Office 365. A green SNDS status doesn't guarantee deliverability across all Microsoft platforms.