It appears that John R Levine via mailop <[email protected]> said: >> Since some mailbox providers are big black boxes that nobody can say how >> they work, it's reasonable to assume that you shouldn't be sending them mail >> that >will bounce, lest you run afoul of some of their other undocumented >rate-limiting, which gives you no feedback even if you sign up for their >postmaster service.
PS: I could see heuristics like not sending DMARC reports to domains hosted at Gmail or Outlook, easy enough with an MX check. If someone is relaying the reports on to Gmail they'll bounce but I expect Gmail will blame the relay, not you. R's, John _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop
