Why doesn't Thunderbird log in mail aka why doesn't it get a response from smtp.yandex.ru?

Question

Yandex

The problem is this.
When transferring user data from Thunderbird from one computer to another, everything becomes great, but an error window pops up like "Waiting for a response from smtp.yandex.ru exceeded".
Took everything down. I installed a bare Thunderberd and went to log in mail. 0 effect. It finds a suitable configuration, and then writes that the login or password is incorrect, or that it cannot check the configuration of the mail account. Although through, directly, the browser - everything goes fine.
In the browser, in the settings of the Yandex mail account, all permissions for mail programs are set.
I tried all the settings provided by Yandex for mail programs.
There is a proxy. Played with the settings in Thunderbird - nothing has changed.
I dug through all the settings. Exposed as on other, normally working computers in a network. Where Thunderbird doesn't kick out. The problem hasn't changed.
Problem with all mailboxes.
I think I'm going crazy. What is this?

Answer 1

It is possible that you have a limitation in the settings of the mail itself on the Yandex server. So it was with me