dotnetcore/CAP · error · InvalidOperationException

You must be config storage provider for…

Error message

You must be config storage provider for CAP!
===================================================================================
========   eg: services.AddCap( options => { options.UseSqlServer(...) }); ========
===================================================================================

What it means

Error "You must be config storage provider for CAP! =================================================================================== ======== eg: services.AddCap( options => { options.UseSqlServer(...) }); ======== ===================================================================================" thrown in dotnetcore/CAP.

Solutions

1. Configure a storage provider in AddCAP, e.g. services.AddCAP(options => { options.UseSqlServer(connectionString); }); (or UseMySql/UsePostgreSql/UseMongoDB/etc.).
2. Ensure the storage extension package (e.g. DotNetCore.CAP.SqlServer) is installed and the Use* method is actually invoked inside the AddCAP options lambda.

When it happens

Trigger: Thrown at src/DotNetCore.CAP/Internal/IBootstrapper.Default.cs:146 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of dotnetcore/CAP@e52b8508e5 (2026-09-14). Data as JSON: /api/errors/ef15a05bb06ab884. Report an issue: GitHub.

Appendix: source

Thrown at src/DotNetCore.CAP/Internal/IBootstrapper.Default.cs:146

    {
        var marker = _serviceProvider.GetService<CapMarkerService>();
        if (marker == null)
            throw new InvalidOperationException(
                "AddCap() must be added on the service collection.   eg: services.AddCap(...)");

        var messageQueueMarker = _serviceProvider.GetService<CapMessageQueueMakerService>();
        if (messageQueueMarker == null)
            throw new InvalidOperationException(
                "You must be config transport provider for CAP!" + Environment.NewLine +
                "==================================================================================" +
                Environment.NewLine +
                "========   eg: services.AddCap( options => { options.UseRabbitMQ(...) }); ========" +
                Environment.NewLine +
                "==================================================================================");

        var databaseMarker = _serviceProvider.GetService<CapStorageMarkerService>();
        if (databaseMarker == null)
            throw new InvalidOperationException(
                "You must be config storage provider for CAP!" + Environment.NewLine +
                "===================================================================================" +
                Environment.NewLine +
                "========   eg: services.AddCap( options => { options.UseSqlServer(...) }); ========" +
                Environment.NewLine +
                "===================================================================================");
    }

    public ValueTask DisposeAsync()
    {
        Dispose();

        return ValueTask.CompletedTask;
    }
}

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