Ask HN: Proofpoint is blocking our emails. Any recourse?

23 points by internet1776 - 273 Days, 14 Hours ago Hacker News

We have a valid email domain that is battletested and used for sending out notifications, invoices, upgrade notices to customers. Our emails goes through all systems and ESP such as Google, Outlook, Proton etc.

However, anytime a customer uses proofpoint they block our emails. I have asked for whitelisting but no reply from them for months. We have SPF, DKIM, DMARC records set. This domain is 2 year old. We run our own email infrastructure – probably only sin we committed so far.

It seems that these companies - Proofpoint, Microsoft, Google - make arbitrary and undisclosed rules for email delivery. Why can't FTC go after these companies and fine them. Microsoft is one of the worst offender. Unless you are a customer of Microsoft and use one of their system, you will face delivery problems.

Either way, does anyone know what can we do for getting past Proofpoint block?