The problem is that you entered the password YES when connecting to the database, but your root password may not have been set yet. Just change YES to a null value.
replyReply Luo Qiemo: First think about the password you set when you installed the database. If you forget it, reinstall it, then $conn = mysqli_connect('127.0.0.1:3306', username, password);
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The problem is that you entered the password YES when connecting to the database, but your root password may not have been set yet. Just change YES to a null value.
Database password error
I told you, access is not allowed. For this kind of problem, you can go to Baidu, there are many