Hi out there
We got two customers (one is another ISP) pretending that they have observed, that Google, Sunrise and other Services have startet flagging their customer's emails as spam, because the sender domain has not SPF record. Not an 'non matching' SPF record, but the sender just dones not use SPF at all.
From my point of view especialy an ISP should be very carefull with SPF. There are hundreds of customers using their email addresses via foreign SMTP Servers. So if you start using SPF als ISP you have to instruct your customers to use SMPT-Auth. Furthermore web based feeback forms and similar would not work anymore if the ip address of that web server is not published as valid sender. And not many mailers who do forward emails are SRS compliant.
So what are your experiences out there? Has someone else observed some ISP having started penalizing emails from sender domains who don't use SPF?
Mit freundlichen Grüssen
Benoit Panizzon