diff --git a/Sio2/SISR/40-ansible/stlab.yml b/Sio2/SISR/40-ansible/stlab.yml
index 9351299..d9810f7 100644
--- a/Sio2/SISR/40-ansible/stlab.yml
+++ b/Sio2/SISR/40-ansible/stlab.yml
@@ -25,6 +25,7 @@
         name: "{{ username }}"
         groups: sudo
         append: yes
+      when: username != ""
 
     - name: installer systemd-journal-remote
       apt: