Report 1251, indicating that the MYSQL version is too low and there is a version difference error with Navicat.
Enter cmd and enter in the command box one by one
mysql -uroot -pEnter
password
use mysql;
select user,host from user;
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '123456';
// My MySQl password is 123456
FLUSH PRIVILEGES;
As shown in the picture
Reconnect to navicat and the connection is successful.
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