Domain of sender address does not resolve support 5 years ago updated 2 years ago Answered Hello, I have problem to send email to domain hosted by your server xxxx.xxxx.iphmx.comWhen I send email to @gtt.net or @eni.com the email remain in queue with this erro:85277628B50 1257 Thu Feb 27 14:36:19 [email protected] | [email protected] | (host mx1.hc3324-5.iphmx.com[68.232.147.154] said: 451 #4.1.8 Domain of sender address does not resolve (in reply to MAIL FROM command))Seem our DNS do not recognise the sender domain @webdesk.it or our sender server smtps.wki.itCan you explain why these messages are blocked?Many thanksDario Lesca for WKI.IT