Sending mail with Yandex SMTP?

Question

Yandex

When sending mail from Yandex (SMTP), WordPress swears: "Could not connect to SMTP server". The mail log on the server gives:

"535 Incorrect authentication data"

Moreover, the login and password are correct. Could it be the lack of an SSL certificate (https) on the site? If yes, is it possible to send mail from the Yandex server using an insecure connection? If you just set the connection type to "none" and port 25, then it gives a 504 error - "Gateway Timeout".

Answer 1

Writes incorrect authentication data, maybe you enter the login incorrectly? Login entirely mail should be.
In general, all mail, that Yandex, that mail ru, that Google, periodically block sendings from the site, everything is automated there, and it’s hard to say what this automation can imagine. Someone has been working for years - then suddenly a blockage. Someone immediately.
Read here, comparison of sending options
https://7fk.ru/nastroyka-smtp/

Answer 2

Yandex before the first sending via smtp requires you to log in via webmail and swear to confirm that you are not a robot. at them in the user agreement it is registered that mail only for people.
and after a while they blurt out that the letters are of the same type and stop accepting mail from vorpress.