We route outbound emails from our website https://www.sameday-delivery.co.uk to O365 Exchange. Our site sits on a dedicated Windows server.
We've recently started to receive undelivered mail notifications (see example below). This appears only to be happening when we are sending to recipients mail-servers which are protected by Mimecast.
Here's some information on how our email delivery is configured which may be useful to know.
IIS
SMTP server configurations are available via the IIS Control Panel namely ‘Internet Information Services (IIS) 6.0 Manager’.
The website/webserver configurations are available via IIS Control Panel namely ‘Internet Information Services (IIS) Manager’.
SMTP EMAIL DELIVERY
The default PHP Mail configurations are pointed to SMTP Virtual Server #1.
This server, configured for ‘mail.samedaydispatch.co.uk’, is responsible for routing all emails from the website to our O365 Exchange.
SMTP CREDENTIALS
There are none. No specific username or password is being used as the server is tied to IP: 77.68.40.223
(Only applications that are hosted at this address can send mail through SMTP Virtual Server #1).
This should be fairly straightforward to fix if you're proficient with the technical aspect of email delivery. Therefore, please don't apply for this posting unless you know what the problem is and how to fix it.
