Drupal – css and js aggregation bug

When css and js are compressed, they are returned to the browser which should unzip them. But when it fails, css design is broken. To fix that follow this : 

Edit settings.php and uncomment the lines : 

$conf[‘css_gzip_compression’] = FALSE;
$conf[‘js_gzip_compression’] = FALSE;

Edit .htaccess and delete this call : 

<IfModule mod_headers.c>