diff --git a/addons/microsoft_calendar/models/calendar.py b/addons/microsoft_calendar/models/calendar.py
index 25195b74b6a2f..bcf734bc99a45 100644
--- a/addons/microsoft_calendar/models/calendar.py
+++ b/addons/microsoft_calendar/models/calendar.py
@@ -229,7 +229,7 @@ def _odoo_attendee_commands_m(self, microsoft_event):
             if email in attendees_by_emails:
                 # Update existing attendees
                 commands_attendee += [(1, attendees_by_emails[email].id, {'state': state})]
-            else:
+            elif partner:
                 # Create new attendees
                 commands_attendee += [(0, 0, {'state': state, 'partner_id': partner.id})]
                 commands_partner += [(4, partner.id)]