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Warning: PDO::__construct(): The server requested authentication method unknown to the client [mysql_old_password]
SQLSTATE[HY000] [2054] The server requested authentication method unknown to the client

I get the error above while trying to connect to my MySQL database server on Hostgator, using a PHP script on my local server. I understand it's a password hashing issue usually between pre MySQL 4.1 and MySQL 4.1+.

I've changed my local server to use the old_password following the instruction I found here.

After changing it to 16 bit hash, I still can not connect, and the error message remains the same. And more so, I can no longer login to phpmyadmin. I'm using XAMPP on windows. Please any suggestions on how to solve these problems?

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1 Answer

up vote 1 down vote accepted

Since you did this changes to the MySQL side, your only other option is to downgrade PHP.

Other links support this:

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Downgrading PHP solved the problem. Thank you very much. –  Chibuzo Mar 10 '13 at 9:55
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