diff --git a/backend/src/models/error.model.ts b/backend/src/models/error.model.ts
index b6c5dfd..10fbd22 100644
--- a/backend/src/models/error.model.ts
+++ b/backend/src/models/error.model.ts
@@ -60,6 +60,14 @@ export const errorRoomNotFound = (roomName: string): OpenViduMeetError => {
 
 // Participant errors
 
+export const errorParticipantUnauthorized = (roomName: string): OpenViduMeetError => {
+	return new OpenViduMeetError(
+		'Participant Error',
+		`Unauthorized generating token with received credentials in room '${roomName}'`,
+		406
+	);
+};
+
 export const errorParticipantNotFound = (participantName: string, roomName: string): OpenViduMeetError => {
 	return new OpenViduMeetError(
 		'Participant Error',
diff --git a/backend/src/services/room.service.ts b/backend/src/services/room.service.ts
index 304bee8..d235446 100644
--- a/backend/src/services/room.service.ts
+++ b/backend/src/services/room.service.ts
@@ -9,6 +9,7 @@ import { OpenViduRoomHelper } from '../helpers/room.helper.js';
 import { SystemEventService } from './system-event.service.js';
 import { TaskSchedulerService } from './task-scheduler.service.js';
 import { ParticipantService } from './participant.service.js';
+import { errorParticipantUnauthorized } from '../models/error.model.js';
 
 /**
  * Service for managing OpenVidu Meet rooms.
@@ -168,7 +169,7 @@ export class RoomService {
 			return ParticipantRole.PUBLISHER;
 		}
 
-		throw new Error('Invalid secret');
+		throw errorParticipantUnauthorized(roomName);
 	}
 
 	/**