diff --git a/scripts/upgrade_prerequisites.sh b/scripts/upgrade_prerequisites.sh
index 28ff626..2e6fdad 100755
--- a/scripts/upgrade_prerequisites.sh
+++ b/scripts/upgrade_prerequisites.sh
@@ -237,7 +237,7 @@ customisation_test()
     local_patchs="$(find /usr/share/eole/creole/patch/ -type f -name "*.patch")"
     if [[ ! -z "${BLACK_LIST}" ]]
     then
-        custom_packages="$(echo $(intersection_list "$(cat $INSTALLED_PACKAGES)" "$BLACK_LIST"))"
+        custom_packages="$(echo $(intersection_list "$(dpkg-query -W -f='${Package}.${Version}')" "$BLACK_LIST"))"
     else
         custom_packages="$(echo $(difference_list "$(cat $INSTALLED_PACKAGES)" "$(cat $VARIANTE_PACKAGES)"))"
         if [[ $USE_DEFAULT == true ]]