I have a 100% no-spam score on mail tester. Have no problem with Gmail server, all users getting my emails. Have everything like SPF and other spam related criteria enabled. Yet, Yahoo mail server keeps deferring my emails, so users can't get them:
SMTP error from remote mail server after pipelined MAIL FROM:<[-----@------.com> SIZE=12259: 421 4.7.0 [TSS04] Messages from [my server IP IP] temporarily deferred due to user complaints - 4.16.55.1; see https://help.yahoo.com/kb/postmaster/SLN3434.html
How can I solve this? I don't think any user complained. it just that another possible reason is that Yahoo is not "used" to see so many emails from my IP. OF course it isn't, I've started offering real time email updates to my users just recently.
