diff --git a/htdocs/install/inc.php b/htdocs/install/inc.php
index e5ad6f019a1..82e9a3dfeaa 100644
--- a/htdocs/install/inc.php
+++ b/htdocs/install/inc.php
@@ -86,7 +86,7 @@ if (! defined('DONOTLOADCONF') && file_exists($conffile))
 		if (empty($dolibarr_main_db_port) && ($dolibarr_main_db_type=='mysqli' || $dolibarr_main_db_type=='mysql')) $dolibarr_main_db_port='3306'; // For backward compatibility
 
 		// Clean parameters
-    	$dolibarr_main_data_root        =isset($dolibarr_main_data_root)?trim($dolibarr_main_data_root):'';
+		$dolibarr_main_data_root        =isset($dolibarr_main_data_root)?trim($dolibarr_main_data_root):DOL_DOCUMENT_ROOT . '/../documents';
     	$dolibarr_main_url_root         =isset($dolibarr_main_url_root)?trim($dolibarr_main_url_root):'';
     	$dolibarr_main_url_root_alt     =isset($dolibarr_main_url_root_alt)?trim($dolibarr_main_url_root_alt):'';
     	$dolibarr_main_document_root    =isset($dolibarr_main_document_root)?trim($dolibarr_main_document_root):'';
@@ -133,7 +133,7 @@ if (! isset($dolibarr_main_db_prefix) || ! $dolibarr_main_db_prefix) $dolibarr_m
 define('MAIN_DB_PREFIX',(isset($dolibarr_main_db_prefix)?$dolibarr_main_db_prefix:''));
 
 define('DOL_CLASS_PATH', 'class/');                             // Filsystem path to class dir
-define('DOL_DATA_ROOT',(isset($dolibarr_main_data_root)?$dolibarr_main_data_root:''));
+define('DOL_DATA_ROOT',(isset($dolibarr_main_data_root)?$dolibarr_main_data_root:DOL_DOCUMENT_ROOT . '/../documents'));
 define('DOL_MAIN_URL_ROOT', (isset($dolibarr_main_url_root)?$dolibarr_main_url_root:''));           // URL relative root
 $uri=preg_replace('/^http(s?):\/\//i','',constant('DOL_MAIN_URL_ROOT'));  // $uri contains url without http*
 $suburi = strstr($uri, '/');       // $suburi contains url without domain