使用navicat 链接MySQL，出现这样的报错：

解决办法：

在服务器上登录mysql ，并且进入 use mysql:

root@localhost 09:07:  [mysql]> update user set host = '%' where user = 'root';
Query OK, 1 row affected (0.07 sec)
root@localhost 09:12:  [mysql]> flush privileges;
Query OK, 0 rows affected (0.02 sec)

 然后再次使用navicat链接出现：

解决办法：

GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'yourpassword' WITH GRANT OPTION

root@localhost 09:13:  [mysql]> GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'yourpassword' WITH GRANT OPTION;
Query OK, 0 rows affected, 1 warning (0.02 sec)

root@localhost 09:14:  [mysql]> flush privileges;
Query OK, 0 rows affected (0.02 sec)

综上：出现这类错误大概是是数据库当中mysql 中root 用户，设置的权限的问题

希望对你有所帮助