mysqlnd cannot connect to MySQL 4.1+ using the old insecure authentication. Please use an administration tool to reset your password with the command SET PASSWORD = PASSWORD(‘your_existing_password’). This will store a new, and more secure, hash value in mysql.user.
使用phpadmin连接上远程数据库，执行以下sql即可：
SET SESSION old_passwords=FALSE;
SET PASSWORD = PASSWORD('yourpassword');