Database connection error (1): The MySQL adapter 'mysqli' is not available
that mean your host don't support MySQLi, you must change it to MySQL
Open configuration.php and change this line:
public $dbtype = 'mysqli';
public $dbtype = 'mysql';
Note: MySQLi mean MySQL Imprved Extension, here all info about it click here.
The main useful features are or MySQLi Extension:
- An Object-oriented interface
- Support for prepared statements
- Support for multiple statements
- Support for transactions
- Enhanced debugging capabilities
- Embedded server support
We sugges to contact your webhosting company to add MySQLi extension on your server.