#6481

src/socket.io/groups.js

@@ -238,6 +238,7 @@ SocketGroups.create = function (socket, data, callback) {
 SocketGroups.delete = isOwner(function (socket, data, callback) {
 	if (data.groupName === 'administrators' ||
 		data.groupName === 'registered-users' ||
+		data.groupName === 'guests' ||
 		data.groupName === 'Global Moderators') {
 		return callback(new Error('[[error:not-allowed]]'));
 	}