MassTransit/MassTransit · error · ConfigurationException

Consumer is excluded from ConfigureEndpoints

Error message

Consumer is excluded from ConfigureEndpoints

What it means

A consumer was explicitly removed from automatic endpoint configuration (ExcludeFromConfigureEndpoints), so calling Endpoint() on its registration configurator is a contradiction: the consumer opted out of ConfigureEndpoints, and per-consumer endpoint customization is only meaningful for consumers included in it. MassTransit throws ConfigurationException to prevent a silently-ignored configuration call.

Solutions

1. Remove the ExcludeFromConfigureEndpoints() call if you want per-consumer Endpoint configuration.
2. Remove the Endpoint(...) call and configure the receive endpoint manually if the consumer must stay excluded.
3. Configure the endpoint inline when adding the consumer, e.g. via AddConsumer with the configure callback and an explicit endpoint definition.

Example fix

// before
x.AddConsumer<OrderConsumer>()
    .ExcludeFromConfigureEndpoints()
    .Endpoint(e => e.PrefetchCount = 10);

// after
x.AddConsumer<OrderConsumer>()
    .Endpoint(e => e.PrefetchCount = 10);

if (consumerRegistration.ExcludeFromConfigureEndpoints)
    throw new InvalidOperationException("Cannot call Endpoint() on a consumer excluded from ConfigureEndpoints.");

try { registration.Endpoint(cfg => cfg.PrefetchCount = 10); }
catch (ConfigurationException ex) { logger.LogWarning(ex.Message); }

When it happens

Trigger: Calling .Endpoint(cfg => ...) on the IConsumerRegistrationConfigurator after having called .ExcludeFromConfigureEndpoints() on the same consumer registration.

Common situations: Copy-pasting registration code where one consumer was excluded from ConfigureEndpoints but still has endpoint customization; refactoring endpoint configuration from automatic to manual without removing the Endpoint() call.

Understand the failure class

Background: Conflicting config options: "cannot be used together" — configuration validation errors across open-source libraries — this error's family across 162 libraries.

Related errors

• The scoped filter could not be added: {TypeCache<TConsumer>.
• Feature is excluded from ConfigureEndpoints
• Saga is excluded from ConfigureEndpoints
• No JSON serializer configured
• A topic consumer with the same key was already added: {speci

AI-assisted analysis of MassTransit/MassTransit@62ab339afa (2026-09-13). Data as JSON: /api/errors/c2f5750b6f04a721. Report an issue: GitHub.

Appendix: source

Thrown at src/MassTransit/DependencyInjection/DependencyInjection/Registration/Consumers/ConsumerRegistrationConfigurator.cs:23

    public class ConsumerRegistrationConfigurator<TConsumer> :
        IConsumerRegistrationConfigurator<TConsumer>
        where TConsumer : class, IConsumer
    {
        readonly IRegistrationConfigurator _configurator;
        readonly IConsumerRegistration _registration;

        public ConsumerRegistrationConfigurator(IRegistrationConfigurator configurator, IConsumerRegistration registration)
        {
            _configurator = configurator;
            _registration = registration;
        }

        public void Endpoint(Action<IEndpointRegistrationConfigurator> configure)
        {
            if (!_registration.IncludeInConfigureEndpoints)
                throw new ConfigurationException("Consumer is excluded from ConfigureEndpoints");

            var configurator = new EndpointRegistrationConfigurator<TConsumer>();

            configure?.Invoke(configurator);

            _configurator.AddEndpoint<ConsumerEndpointDefinition<TConsumer>, TConsumer>(_registration, configurator.Settings);
        }

        public void ExcludeFromConfigureEndpoints()
        {
            _registration.IncludeInConfigureEndpoints = false;
        }
    }
}

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