RabbitMQ Connection Error " None of the specified endpoints were reachable"

I was also facing the same issue and later realized I have to open both ports i.e. 15672 and 5672.

The below command works for me in the docker container model.

docker run -it --rm --name mymq -p 5672:5672 -p 15672:15672 rabbitmq:3-management

Code snippet:

 var factory = new RabbitMQ.Client.ConnectionFactory
            {
                Uri = new Uri("amqp://guest:guest@localhost:5672/")
            };

or

var factory = new ConnectionFactory() { HostName = "localhost" };

Do not use guest. Create your own account and password, and in http://localhost:15672/#/users , ensure "can access virtual hosts " is "/"

var factory = new ConnectionFactory() { 
  HostName = "192.168.1.121",
  Port = 5672,
  UserName = "fancky", 
  Password = "123456" 
};

Thank you all. As this :
https://stackoverflow.com/questions/4987438/rabbitmq-c-sharp-connection-trouble-when-using-a-username-and-password
After I installed RabbitMQ, I enabled management tools at the server and on my local computer with this:

rabbitmq-plugins enable rabbitmq_management

Then I restarted RabbitMQ service from services.msc
I could see the rabbitmq management at http://localhost:15672
I loginned to rabbit management with user:guest and pass:guest
I added my favorite user pass with administrator access, so it worked.


In our case it was an assembly binding failure of System.Threading.Tasks.Extensions, our exception logger was not logging the InnerException

Exception information: 
    Exception type: FileLoadException 
    Exception message: Could not load file or assembly 'System.Threading.Channels, Version=4.0.2.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
   at RabbitMQ.Client.Framing.Impl.AutorecoveringConnection..ctor(ConnectionFactory factory, String clientProvidedName)
   at RabbitMQ.Client.ConnectionFactory.CreateConnection(IEndpointResolver endpointResolver, String clientProvidedName) in /_/projects/RabbitMQ.Client/client/api/ConnectionFactory.cs:line 494

Very poor misleading error message.