diff --git a/usr/share/archboot/installer/setup b/usr/share/archboot/installer/setup
index 10ee2b8a8..148c7219b 100755
--- a/usr/share/archboot/installer/setup
+++ b/usr/share/archboot/installer/setup
@@ -264,12 +264,13 @@ manual_media() {
 destdir_mounts(){
     # Don't ask for filesystem and create new filesystems
     ASK_MOUNTPOINTS=""
+    PART_ROOT=""
     # check if something is mounted on $DESTDIR
-    [ "$PART_ROOT" = "" ] && PART_ROOT="$(mount | grep "$DESTDIR " | cut -d' ' -f 1)"
+    PART_ROOT="$(mount | grep "$DESTDIR " | cut -d' ' -f 1)"
     # Run mountpoints, if nothing is mounted on $DESTDIR
     if [ "$PART_ROOT" = "" ]; then
         DIALOG --msgbox "Setup couldn't detect mounted partition(s) in $DESTDIR, please set mountpoints first." 0 0
-        mountpoints || (PART_ROOT=""; return 1)
+        mountpoints || return 1
     fi
 }