I created a filter in roundcube to block some annoying senders:
I want to let them know they are blocked, so they should receive that message, but it’s not delivered because of the following error (I made a test from my gmail):
Oct 21 13:38:43 mail postfix/smtp: 112DD1B91F1: to=XXXX@gmail.com, relay=gmail-smtp-in.l.google.com[2a00:1450:400c:c06::1b]:25, delay=0.46, delays=0.06/0.02/0.18/0.19, dsn=5.7.26, status=bounced (host gmail-smtp-in.l.google.com[2a00:1450:400c:c06::1b] said: 550-5.7.26 Unauthenticated email from YYYY.com is not accepted due to 550-5.7.26 domain’s DMARC policy. Please contact the administrator of 550-5.7.26 YYYY.com domain if this was a legitimate mail. Please 550-5.7.26 visit 550-5.7.26 Control unauthenticated mail from your domain - Gmail Help to learn about the 550 5.7.26 DMARC initiative. m16si7007031wmg.78 - gsmtp (in reply to end of DATA command))
DMARC policy is
v=DMARC1; p=reject and other emails are delivered without issues. Why roundcube is sending this message without proper authentication? Is there a way to fix this?