I use Outlook to manage my mail and all my addresses are pulled into Outlook. Mostly I respond to mail on the web application or through Outlook on a desktop. My problem is replying to mail on my windows phone. The emails seem to send OK but i then get a mail from firstname.lastname@example.org with a delivery status notification delay) which eventually turns into a fail. The message attached to the delay is Reporting-MTA: dns;DUB004-WSS1S6.hotmail.com Received-From-MTA: dns;DUB404-EAS82 Arrival-Date: Tue, 2 Dec 2014 09:20:19 -0800 Final-Recipient: rfc822;address@domain Action: delayed Status: 4.4.7 Will-Retry-Until: Thu, 4 Dec 2014 09:20:20 -0800 I suspect the problem occurs on mail that were originally sent to my plusnet address and pulled into hotmail, as I'm replying with a hotmail address. Windows phne doesn't allow you to chose the account to reply from. I try and remember to forward rather than reply ( that seems to be OK ) but I'm forgetful and intuitively its easy to hit reply when that's what you want to do. Hope that's not too garbled. any help gratefully received.