diff --git a/plugins/admidio_events/admidio_events.py b/plugins/admidio_events/admidio_events.py
index dba3d09..44c601a 100644
--- a/plugins/admidio_events/admidio_events.py
+++ b/plugins/admidio_events/admidio_events.py
@@ -282,53 +282,56 @@ class Plugin:
             room.send_html(self.messages['info_event_id_err'])
             return
 
-        # Set header
-        html_message = self.messages['event_participants_head'].format(
-            len(self.adm.events[id_event].getAllAttend()),
-            self.adm.events[id_event].number_of_guests,
-            self.adm.events[id_event].name)
+        try:
+            # Set header
+            html_message = self.messages['event_participants_head'].format(
+                len(self.adm.events[id_event].getAllAttend()),
+                self.adm.events[id_event].number_of_guests,
+                self.adm.events[id_event].name)
 
-        # Attend
-        html_message += "<br />"
-        html_message += self.messages['event_participants_attend'];
+            # Attend
+            html_message += "<br />"
+            html_message += self.messages['event_participants_attend'];
 
-        # Loop through fetched participants
-        html_message += "<ul>"
+            # Loop through fetched participants
+            html_message += "<ul>"
 
-        for member in self.adm.events[id_event].getAllAttend():
-            html_message += "<li>"
-            html_message += member[1].username
-            html_message += "</li>"
+            for member in self.adm.events[id_event].getAllAttend():
+                html_message += "<li>"
+                html_message += member[1].username
+                html_message += "</li>"
 
-        html_message += "</ul>"
+            html_message += "</ul>"
 
-        # Maybe
-        html_message += self.messages['event_participants_maybe'];
+            # Maybe
+            html_message += self.messages['event_participants_maybe'];
 
-        # Loop through fetched participants
-        html_message += "<ul>"
+            # Loop through fetched participants
+            html_message += "<ul>"
 
-        for member in self.adm.events[id_event].getAllMaybe():
-            html_message += "<li>"
-            html_message += member[1].username
-            html_message += "</li>"
+            for member in self.adm.events[id_event].getAllMaybe():
+                html_message += "<li>"
+                html_message += member[1].username
+                html_message += "</li>"
 
-        html_message += "</ul>"
+            html_message += "</ul>"
 
-        # Not attend
-        html_message += self.messages['event_participants_not_attend'];
+            # Not attend
+            html_message += self.messages['event_participants_not_attend'];
 
-        # Loop through fetched participants
-        html_message += "<ul>"
+            # Loop through fetched participants
+            html_message += "<ul>"
 
-        for member in self.adm.events[id_event].getAllNotAttend():
-            html_message += "<li>"
-            html_message += member[1].username
-            html_message += "</li>"
+            for member in self.adm.events[id_event].getAllNotAttend():
+                html_message += "<li>"
+                html_message += member[1].username
+                html_message += "</li>"
 
-        html_message += "</ul>"
+            html_message += "</ul>"
 
-        room.send_html(html_message)
+            room.send_html(html_message)
+        except KeyError:
+            room.send_html(self.messages['unknown_event'])
 
     def chat_callback(self, room, event):
         room.send_text("Chat")