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Sam (UK) sent an invoice that bounced 7 Nov 2026 with AS9031519. Sam has SPF but no DMARC. Priya (UK) sends a newsletter via an ESP. Gmail returned 550-5.7.26; SPF passes for the ESP bounce domain and DKIM is signed by the ESP, so neither aligns with the From domain. Tom (UK) runs a small shop sending 6,000 messages/day. Outlook returned 5.7.515 and the SPF record needs 11 DNS lookups, over the limit of 10.
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