This might be old news, but we started seeing delivery deferrals to Gmail starting Nov 13 around 4pm EST. It started at about 10% of deliveries, mostly affecting larger accounts, and all having IP and domain reputations in Google Postmaster Tools of high and medium. Messages were delivered on subsequent retries.
Last night, when the deferrals increased to 25-30%, we deployed TLS for deliveries, and the deferrals immediately went to zero. Hope that helps others. Omar -- BIGLIST.com _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop
