Fill in your database details, then upload the file via ftp, overwriting the old one.
Im not sure why your dragging and dropping files, but i would edit directly from the server, then resave it to the server.
Code:
<?php
$config['Database']['dbtype'] = 'mysql';
$config['Database']['dbname'] = '';
$config['Database']['tableprefix'] = '';
$config['Database']['technicalemail'] = '';
$config['Database']['force_sql_mode'] = false;
$config['MasterServer']['servername'] = 'localhost';
$config['MasterServer']['port'] = 3306;
$config['MasterServer']['username'] = '';
$config['MasterServer']['password'] = '';
$config['MasterServer']['usepconnect'] = 0;
$config['SlaveServer']['servername'] = '';
$config['SlaveServer']['port'] = 3306;
$config['SlaveServer']['username'] = '';
$config['SlaveServer']['password'] = '';
$config['SlaveServer']['usepconnect'] = 0;
$config['Misc']['admincpdir'] = 'admincp';
$config['Misc']['modcpdir'] = 'modcp';
$config['Misc']['cookieprefix'] = 'bb';
$config['Misc']['forumpath'] = '';
$config['SpecialUsers']['canviewadminlog'] = '1';
$config['SpecialUsers']['canpruneadminlog'] = '1';
$config['SpecialUsers']['canrunqueries'] = '1';
$config['SpecialUsers']['undeletableusers'] = '1';
$config['SpecialUsers']['superadministrators'] = '1';
//$config['Datastore']['class'] = 'vB_Datastore_XCache';
//$config['Datastore']['prefix'] = 'at_';
/*
$config['Datastore']['class'] = 'vB_Datastore_Memcached';
$i = 0;
// First Server
$i++;
$config['Misc']['memcacheserver'][$i] = '127.0.0.1';
$config['Misc']['memcacheport'][$i] = 11211;
$config['Misc']['memcachepersistent'][$i] = true;
$config['Misc']['memcacheweight'][$i] = 1;
$config['Misc']['memcachetimeout'][$i] = 1;
$config['Misc']['memcacheretry_interval'][$i] = 15;
*/
// $config['Mysqli']['charset'] = 'utf8';
$config['Mysqli']['ini_file'] = '';
$config['Misc']['maxwidth'] = 2592;
$config['Misc']['maxheight'] = 1944;