Am Wed, Feb 07, 2024 at 06:41:48AM -0900 schrieb Royce Williams via mailop: > There are multiple reports on Reddit and other places of people getting the > explicit "authentication required" SMTP response at much lower volumes. > I've also experienced it directly myself, on domains that I directly > control that don't do 50 a day, let alone 5000.
Can you confirm that these domains had a valid SPF record? Would you mind sharing the exact value of the SPF? _______________________________________________ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
