diff --git a/41_snapshots-btrfs b/41_snapshots-btrfs
index c864b84..9cd58fa 100644
--- a/41_snapshots-btrfs
+++ b/41_snapshots-btrfs
@@ -575,3 +575,7 @@ EOF
 else
     print_error "Syntax errors are detected in generated grub-btrfs.cfg file."
 fi
+
+# warn when this script is run but there is no entry in grub.cfg
+grep "snapshots-btrfs" "${grub_directory}/grub.cfg" || printf "\nWARNING: '%s' needs to run at least once to generate the snapshots (sub)menu entry in grub the main menu. \
+After that this script can run alone to generate the snapshot entries.\n\n" "${GRUB_BTRFS_MKCONFIG:-grub-mkconfig}" >&2 ;