ALTOSPAM has developed a very useful tool freely accessible on the Internet at: https: //www.altospam.com/outil/ to simulate the entire e-mail simulation procedure (detailed in our article %E2%.
Using this tool, the test, which is not performed from your mail server (as described in the above article), nevertheless gives a very good indication of the configuration of the remote domain or recipient.
This tool has two functions:
1- if you specify a domain name: it analyzes the integrity of the mail service configuration of the domain concerned.
2- if you enter a full email address: in addition to analyzing the DNS zone for the email service, it will simulate the sending of an email for you.
In both cases:
– It checks the consistency of the “Whois” with the NS defined at DNS zone level,
– It lets you check that your DNS servers are properly synchronized,
– It lets you check which mail servers manage the domain in question (this query is made directly to the authoritative DNS servers, so as to be independent of any DNS propagation concerns),
– It also checks for each IP (DNS and mail servers) the DNS reverses configured and their bijectivity (arrows <-> reciprocal between the server name and its IP address) as well as the country of attachment of the IP concerned.
In the second case :
– It returns a code 250 “RCPT TO OK” if the user exists.
– or a code 5xx if the user is unknown (for example).
CAUTION however, there are two cases in which the system may give you a 2xx code even though the address is invalid: when the recipient server is configured to “catch all” or when the server does not filter recipients but Bounces (see our article https://www.altospam.com/actualite/2008/09/configuration-des-serveurs-de-messagerie-et-filtrage-des-destinataires/ ).
As explained at the bottom of the https://www.altospam.com/outil/ page, you can also offer this service free of charge on your website, so that it’s available to your visitors.