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civerell

civerell peringne
Network

iChat

Network Mar 04 2015
Score 52%
52 Likes
48 Dislikes

Composer

Network Mar 04 2015
Score 52%
52 Likes
48 Dislikes
Browser

Facebook X

Browser Sep 09 2013
Score 52%
52 Likes
48 Dislikes
System Software

qGrid

System Software Aug 16 2015
Score 52%
52 Likes
48 Dislikes
Utilities

jamx

Utilities Dec 19 2017
Score 50%
50 Likes
50 Dislikes
Composer

Network 4 comments

Score 52%
52 Likes
48 Dislikes
Mar 04 2015
MX Record is done not for the computer, but for the network interface. And it is done not on the local computer, but in the DNS system of the Internet.

How things work. When you send a mail, your host uses MX record to locate the target mail server. And the target mail server uses MX record of the source mail domain to check if the sender is legitimate mail sender of the source domain. These are different MX records and both are handled by the DNS. Google (for example) manages MX record for gmail and you have to manage MX for your server.

There is a free opportunity to do that. You can go to no-ip.com and register a hostname for your computer. There you'll optain a free host name. And that'd be the name, that'd point to your computer will be an "A" DNS record. Also, there is a feature, that allows you to additionally make a "MX" record for your computer name. Then you'll be able to legitimately operate with @hostname mails.

("A" record just allows hosts in the internet to convert your hostname to ip address. "MX" record tells the hosts in the internet what server they have to use to send mail to you.) - Oct 10 2015
You see, the error message you get is not generated by Composer. It is recieved as a response to a mail send request from the target mail server.

Today mail servers do not usually accept any incoming mail they get. For example your mail gets rejected if you send mail from user1@gmail.com to user2@gmail.com, because this kind of mails doesn't go through smtp. Also, there are special trusted tunnels between well known mail services and thus mail from user1@yandex.ru won't be delivered to user2@mail.ru by Composer, because those domains have a dedicated tunnel between them and mail messages don't go through smtp.

To have a more reliable delivery you have to have a sender mail domain that is not known to the target mail domain. And you'd also want to set up an MX record of the sender domain to the ip address to the computer, from which you send mails. If you do those things, your messages are very likely to be delivered without errors. - Oct 10 2015