Your PHP installation appears to be missing the MySQL extension which is required by WordPress.

This error has a history that goes back years. I have never experienced it before. A WordPress account for some unknown reason stops working on one server. The IP won't ping so it appears to be a network issue, Apache issue?? - something I have no clue about.

Moving a backup to another server and this "missing the MySQL extension error" is generated when trying to display the website, but at least the IP is pinging now. All server are using PHP version 5.3.3. I did look for in the php.ini file for either an entry for extension=mysql.so or extension=mysqli.so - I did not find one but new WordPress sites install fine and everything is working as expected. I thought maybe the extension was commented out but it is not there at all. I am just not sure where to go from here. Any suggestion would be most welcome.