Determine if you can copy from the default exchange.

CopyFromDefaultExchangeProgram.cs

using RabbitMQ.Client;
using RabbitMQ.Client.Events;
using System;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace RabbitMQPOCs
{
    class Program
    {
        static void Main(string[] args)
        {
            // need to start a docker container and change the IP to the container IP below
            // e.g. docker run -d -p 15672:15672 -p 5672:5672 -p 5671:5671 rabbitmq:3-management

            var factory = new ConnectionFactory() { HostName = "172.19.109.180" };
            using (var connection = factory.CreateConnection())
            {
                using (var consumerChannel = connection.CreateModel())
                {
                    ConsumeMessages(consumerChannel);
                    CopyToExchange(connection);

                    PublishMessages(connection);
                }
            }
        }

        private static void PublishMessages(IConnection connection)
        {
            using (var channel = connection.CreateModel())
            {
                string message = "Hello World";
                do
                {
                    Console.WriteLine(" Enter a message or nothing to stop.");
                    message = Console.ReadLine();


                    PublishMessage(message, channel);

                    

                } while (!string.IsNullOrWhiteSpace(message));
            }
        }

        private static void CopyToExchange(IConnection connection)
        {
            // lets see if we can copy messages from the default exchange to a new exchange
            // theory is you can subscribe to the default exchange
            /*
             And you cannot:
             RabbitMQ.Client.Exceptions.OperationInterruptedException: 
             'The AMQP operation was interrupted: AMQP close-reason, initiated by Peer, code=403,
             text="ACCESS_REFUSED - operation not permitted on the default exchange",
             classId=40, methodId=30, cause='
             */
            using (var channel = connection.CreateModel())
            {
                channel.ExchangeDeclare("copyofdefault", "fanout", false, true);

                channel.ExchangeBind("copyofdefault", "", "task_queue");

                var qd = channel.QueueDeclare(exclusive: true);

                channel.QueueBind(qd.QueueName, "copyofdefault", "");

            }
        }

        private static void ConsumeMessages(IModel channel)
        {


                channel.QueueDeclare(queue: "task_queue",
                                durable: true,
                                exclusive: false,
                                autoDelete: false,
                                arguments: null);

                channel.BasicQos(prefetchSize: 0, prefetchCount: 1, global: false);

                Console.WriteLine(" [*] Waiting for messages.");

                var consumer = new EventingBasicConsumer(channel);
                consumer.Received += (model, ea) =>
                {
                    var body = ea.Body;
                    var message = Encoding.UTF8.GetString(body);
                    Console.WriteLine(" [x] Received {0}", message);

                    int dots = message.Split('.').Length - 1;
                    Thread.Sleep(dots * 1000);

                    Console.WriteLine(" [x] Done");

                    channel.BasicAck(deliveryTag: ea.DeliveryTag, multiple: false);
                };
                channel.BasicConsume(queue: "task_queue",
                                        autoAck: false,
                                        consumer: consumer);

        }

        private static void PublishMessage(string message, IModel channel)
        {
            var body = Encoding.UTF8.GetBytes(message);

            var properties = channel.CreateBasicProperties();
            properties.Persistent = true;

            channel.BasicPublish(exchange: "",
                                 routingKey: "task_queue",
                                 basicProperties: properties,
                                 body: body);
        }
    }
}