In my experience, MS and others give you a chance to correct the issue and if you don't do so in a …
In my experience, MS and others give you a chance to correct the issue and if you don't do so in a timely manner (which requires qualified help), or it isn't corrected, then you get blackholed thereafter, and will remain that way up to years afterwards. There is very little interaction from them, they assume you'll be professional enough to read the published literature and act accordingly. The literature is a way of adding cost to those that would send spam, it also adds cost in other ways. If I had to guess without knowing more, assuming you've correctly configured yourself locally (which may not actually be the case), I'd say it could be because of your ISP. In recent years, with the depletion and exhaustion of IPv4 address space, many ISPs have moved towards CGNAT, where multiple customers share the same IP transparently. The ISP may do this without you knowing, but you'd have to have constructive knowledge in some fine print. Subsequently by extension, they share the same reputation characteristics for that portion as others on the same network. …
Original discussionSpammers are better at SPF, DKIM, and DMARC than everyone else253 source comments · at import