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Our website is sending out email verifications to members who sign up with our service.
Yahoo is throwing our messages in the spam box and displaying this message in the headers:
Received-SPF: none (domain of -.com does not designate permitted sender hosts)
I'm pretty sure this is the reason why.
I added a text record to our DNS:
v=spf1 mx:smtp.secureserver.net +all
Maybe I didn't set it up right? The yahoo message remains.
Our email has html and text versions and has received a score of .07 on spamassassin, so I highly doubt that anything in the email content itself is throwing a flag.