diff --git a/acrobat-plugin/src/Imposition-00-Core.js b/acrobat-plugin/src/Imposition-00-Core.js
index 788706b..1ade93f 100755
--- a/acrobat-plugin/src/Imposition-00-Core.js
+++ b/acrobat-plugin/src/Imposition-00-Core.js
@@ -241,7 +241,7 @@ try {
         cName: "CDImpLivret",
         cUser: "Livret / Delivretiser",
         cParent: "ImpositionPro",
-        cExec: "if(CDImp.Livret&&CDImp.Livret.lancer)CDImp.Livret.lancer(event.target);",
+        cExec: "try{app.alert('Livret: lancement...');CDImp.Livret.lancer(event.target);}catch(e){app.alert('Erreur: '+e);}",
         cEnable: "event.rc = true;",
         nPos: 0
     });