O.S.: Ubuntu Linux server 10.04, PHP Version 5.4.34-1+deb.sury.org~lucid+1
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PHP has not been properly configured with the MySQLi extension so that it can communicate with MySQL. Please check your php.ini file or recompile PHP. MySQLi extension is not available for PHP 4.
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Rešenje:
1. Reinstalirati libapache2-mod-php5
apt-get purge libapache2-mod-php5 php5 && \ apt-get install libapache2-mod-php5 php5
2. Ponovo instalirati:
sudo apt-get install php5-mysql
sudo apt-get install php5-mysqlnd
3. Restartovati Apche i MySQL.
sudo /etc/init.d/apache2 restart
sudo /etc/init.d/mysql restart