This may be because not all domain name system servers (DNS) have been informed that your domain's MX records are pointing to our servers. Propagation of information about changes to MX-records may take between a few hours and 2-3 days.
In addition, make sure that you have configured the MX records correctly. Use nslookup services on the Internet to see what MX record value your domain provides:
An MX record with an mx.yandex.net. address must be unique or it should have the highest priority compared to the other records;
if in following the verification results the MX record does not appear as mx.yandex.net., but as mx.yandex.net.domain.tld (where domain.tld is the name of your domain), place a dot in the domain settings of the hosting provider at the end of the address: mx.yandex.net.
If the domain is configured correctly but emails still do not arrive, check if the email sender receives an automatic server response. The reasons why the emails are not delivered will be indicated there. In the special Help section we have tried to compile all possible mail non-delivery reports which users receive.
If there is no automatic response, the problem might be on the senders' servers, or on our servers when receiving emails. In this case, please contact your mail administrator. To be able to identify whether the email has reached our servers, we need either the full e-mail headers of the sent emails or the delivery logs of this email, which can only be provided by the administrator of the sender's server.
Maybe you sent a bulk mail which was identified as spam by our servers or the recipient's servers. Please read our recommendations on "honest mailings".
In addition, we urgently recommend that you customize the SPF records of your domain, which will inform the server of the receiver that Yandex servers are authorized to send email on behalf of your domain.
If you receive non-delivery reports detailing other reasons for non-delivery (different from spam), check the corresponding article in our help.
Some users face the following problem: after configuring some feedback forms or just the automatic notifications on their website, these emails do not arrive at the address of the Mail for domains if the domain matches the website address.
This is because for the server where the website is located, your domain is a local one; therefore, the server tries to send emails to an internal directory. Meanwhile, you are waiting for the emails to arrive at the mailbox on the Yandex server. You can contact the administrator of the server where the website is located and ask for the server settings to be corrected. It is essential that the server send emails in accordance with the domain's MX records. If you have an active mail service on the hosting where your website is located, you can disable it.
You can also try to configure the mail delivery through our SMTP server, smtp.yandex.com, using port 25 (main) or 587 (backup) and mandatory authentication on the server. For mail delivery, you have to configure the input of the full address of the mailbox which is used as a login for mail delivery and its password. Mail delivery can also be performed by SSL through the connection to port 465.
To avoid problems with mail delivery, the mailing must comply with the guidelines on "honest mailings".