I have created a Shopping Cart, would like to use PayPal to handle transactions and believe a server side email is required.
I followed a tutorial that uses Postfix and created a test email using PHP mail(…); and the returned result was true… unfortunately where it went I do not know but it was not to the required destination address
I also tried sending an email from Gmail and a delivery failure was reported stating an incorrect MX value was encountered.
Searching for the correct MX value was not successful.
DNS Error: 1235394 DNS type ‘mx’ lookup of joe-blogs.com responded with code NOERROR 1235394 DNS type ‘aaaa’ lookup of mail.joe-blogs.com. responded with code NXDOMAIN 1235394 DNS type ‘a’ lookup of mail.joe-blogs.com. responded with code NXDOMAIN
I can recommend not dealing with mail sending yourself, but instead using a solution like Mailgun, Amazon SES, Sendgrid, etc. to do the heavy lifting for you.
Sure, it costs a few dollars a month, but compared to having to keep a mail server running, configuring and maintaining SPF, DKIM, making sure your server doesn’t end up being marked as a spammer, etc, etc, it’s well worth it.