Hello @StephenW223 ,
Our Delivery team, Compliance, and several other background technical teams work directly with major email providers to figure out the best compromises between their needs and security protocols, and the needs of our customers for communications and marketing. This means that there may be things that customers need to do on their end to make the processes work. This can be things like self-authentication, making sure emails avoid words and phrasing that can trip up spam filters, and perform other best practices to maintain sending reputation.
Additionally, these specialized teams also work with the major providers to ensure previous damages to sending reputation from bad actors is repaired, and that we implement automated and manual protocols on our side to prevent further bad actors from using our system. This is why we have a Review team, why spam reports and large numbers of unsubscribes are taken very seriously, and why we now require multi-factor authentication for all logins.
If an organization has their security programs set to filter out third party email service providers (another reason we suggest having your own domain and using self-authentication), then no amount of us "lobbying" the service they use will overcome that without additional email authentication and/or safelisting our domains / your email addresses. This is standard across the industry, and is something that all ESPs regularly contend with to ensure deliveries.
Other elements, such as a customer's email address sending reputation, are outside of our control. It's why some accounts will be closed by our automated Compliance systems immediately upon creation, such as specific email addresses, problematic domains, or IP addresses with negative reputations. These negative reputations are tracked throughout the internet, and are considered by all email programs when an email is received by them from those sources.
If you're particularly concerned about your emails being sorted into spam, or you have any questions about any of the above points, I'd advise speaking with our Delivery team directly for specialized insight, assistance, and troubleshooting.
See also:
Review and Compliance FAQ
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William A
Community & Social Media Support