Hi we are running a application which sends notification as email-to-sms. For t-mobile receipients notifications are getting bounced while for ATT & Verizon its working fine.
here is the error log on our mail server
to=<929920XXXX@tmomail.net>, relay=d79033a.ess.barracudanetworks.com[188.8.131.52]:25, delay=2.7, delays=0/0/0.49/2.2, dsn=5.0.0, status=bounced (host d79033a.ess.barracudanetworks.com[184.108.40.206] said: 550 permanent failure for one or more recipients (929920XXXX@tmomail.net:550 Rejecting for Sender Policy Framework) (in reply to end of DATA command))
Our domain has SPF record and other checks inline. I suspect something is at t-mobile mail server which is blocking messages.
Any one has any context on this.
*edited to remove personal information - Marissa
Best answer by tmo_laurenView original