To open the mailbox login page, go to the address “https://mail.yandex.ru/?pdd_domain=уourdomain.tld”, where “yourdomain.tld” is the name of the domain where the mailbox was created.
For the username, enter the mailbox name (the part of the email address that comes before the “@” symbol). For example, for the mailbox “firstname.lastname@example.org”, enter the username “login”.
You can also set up access to the login page at the address “mail.yourdomain.com”, where “yourdomain.com” is the name of the domain where the mailbox was created. To do this, you need to set up a corresponding CNAME record on the domain hosting servers.