diff --git a/src/setup.php b/src/setup.php
index ef33098..a3c1b04 100644
--- a/src/setup.php
+++ b/src/setup.php
@@ -336,6 +336,9 @@ function testConnect(&$error)
 	{
 		if(Config::get('db') == 'mysql')
 		{
+			if ( !function_exists("mysqli_connect") ) {
+				throw new Exception("Required PHP extension 'mysqli' is not installed");
+			}
 			require_once(MTTINC. 'class.db.mysql.php');
 			$db = new Database_Mysql;
 			$db->connect(Config::get('mysql.host'), Config::get('mysql.user'), Config::get('mysql.password'), Config::get('mysql.db'));