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Unverifiable area
Any domain that sends emails must be able to receive them.
Some emailings come from email addresses that don’t really exist, such as noreply@domaine.tld. This allows the sender to avoid receiving bounces from mail servers that have refused the message. On the other hand, a sender’s domain (in our previous example: domain.tld) must always be able to receive emails. if only on the postmaster address to contact the e-mail manager or to report abuse (receipt of spam from the domain) on the address: abuse@domaine.tld. It is therefore perfectly legitimate to check that the domain sending an email is able to receive emails.
At ALTOSPAM, like many other mail servers on the Internet, we check the sender’s domain as soon as an email arrives. To do this, we perform an MX query on the DNS of the sending domain to ensure that it is able to receive emails.
An “Unverifiable Domain” is therefore :
– Or a sender domain with no MX fields configured in its DNS. If the sender is legitimate, all he needs to do is create an MX field on the domain used to send emails. But generally speaking, if he sends you an email, it’s because he’s also capable of receiving one!
– A domain with one or more IP addresses as MX fields. This is strictly forbidden according to RFC2821. A domain’s MX fields must point to an FQDN host name, not an IP. To solve the problem, all your sender has to do is create a host name (by creating an A field) pointing to the IP in question and replace the IP address specified at MX level with the newly created host name.
– Last possibility: the MX field of the domain does point to an FQDN host name, but this host name is not assigned to any legitimate IP. It doesn’t make sense to set an MX field to a host name: server.domain.tld if it doesn’t point to an IP, normally that of the mail server able to handle emails from the domain in question.
If your mail server tells you that the ALTOSPAM server is refusing your e-mail because “Domain not verifiable”, it’s because of one of the above-mentioned configuration errors. To check your domain configuration, we invite you to test it using our online tool: https: //www.altospam.com/outil/
We remind you that all this is based on the fact that it makes no sense to receive an email from someone who is unable to receive one.
