Why 404 when going to another page?

Question

WordPress

There is a site that was previously on https://sait.ru/, now it is on http://old.sait.ru/
PHPMyAdmin is indicated everywhere http://old.sait.ru/
All links on the site look like http://old.sait.ru/......
.htacess is empty.
Question:
Why do I get 404 when I go to any other page on the site?

Answer 1

Treatment:
Update permalinks in WP itself

Answer 2

because you have to lift your eyes to the browser's address bar, look at the link, and figure out what's wrong with it.
if the letter old is missing there, then this means that not all links on the site look like old.sait.ru
You just listened to the basic course of everyday logic for elementary grades