diff --git a/htdocs/includes/fpdf/fpdf/fpdf.php b/htdocs/includes/fpdf/fpdf/fpdf.php
index b5604008be8..f604c62a94f 100644
--- a/htdocs/includes/fpdf/fpdf/fpdf.php
+++ b/htdocs/includes/fpdf/fpdf/fpdf.php
@@ -12,7 +12,7 @@
 // height of cell repect font height
 define("K_CELL_HEIGHT_RATIO", 1.25);
 // Répertoire des documents de fckeditor
-define ("K_PATH_CACHE", $conf->fckeditor->dir_output);
+if (! empty($conf->fckeditor->dir_output)) define ("K_PATH_CACHE", $conf->fckeditor->dir_output);
 // url qui sera substituer par le K_PATH_CACHE lorsqu'une image sera intégrée au pdf
 if (defined('DOL_URL_ROOT')) define ("K_PATH_URL_CACHE", DOL_URL_ROOT."/document.php?modulepart=editor&file=");
 /* End DOLCHANGE Added by Regis */