Make sure that you have configured the domain correctly. Configuration instructions are provided in the How do I confirm domain ownership? section. If you are confirming the domain ownership by loading a special file, make sure that you placed the file in the root directory of the website and it is available to view.
For example, the file for domain yasupport.ru must be accessible via the link http://yasupport.com/79e8c0eb5831.html.
It is possible that your hosting provider has not yet made the changes to the zone settings, or they are not yet valid. Check with the support service of the domain DNS hosting.
We also advise that you check that all fields in the DNS server domain management interface are filled in correctly. Make sure that you have deleted all previous MX records and there is a dot at the end of the mx.yandex.net. address.
More detailed information on configuring MX records are provided in the section How to configure MX records
This might happen if you try to delegate the domain before you actually confirm domain ownership. Unless you confirm domain ownership, there will be no SOA records generated on our servers which prove the readiness to "accept" the domain.
Domain ownership confirmation will enable the correct generation of SOA records and it will ensure that DNS domain settings and mailboxes are managed with your login.
If you cannot use any of the methods listed on the Help page for domain ownership confirmation, try to delegate the domain without testing, if this is allowed by your registrar.
Yandex.Mail for domains is a Yandex service. To connect your domain to Yandex Mail, you need a Yandex account, which will be your administration account. You will use this account to manage the mailboxes which are created on the basis of your domain.
Email and mailboxes can only be managed through the account the domain is connected to. We therefore recommend that you register a separate (not a personal) account to connect a corporate domain. Please note that account access can only be restored if you have provided additional personal information (security question, mobile phone number, additional mail address, full name and other data) in Yandex.Passport. Please make sure that all information is true and correct, you have access to the additional email address or mobile phone, and can also answer the security question.