abpframework/abp · error · ArgumentException

Given module instance ({instance.GetType().AssemblyQualified

Error message

Given module instance ({instance.GetType().AssemblyQualifiedName}) is not an instance of given module type: {type.AssemblyQualifiedName}

What it means

Thrown by the AbpModuleDescriptor constructor when the IAbpModule instance passed in is not assignable to the declared module Type. ABP asserts type identity of a module instance at descriptor-creation time. It is an ArgumentException reporting both type names.

Source

Thrown at framework/src/Volo.Abp.Core/Volo/Abp/Modularity/AbpModuleDescriptor.cs:35

    public IAbpModule Instance { get; }

    public bool IsLoadedAsPlugIn { get; }

    public IReadOnlyList<IAbpModuleDescriptor> Dependencies => _dependencies.ToImmutableList();
    private readonly List<IAbpModuleDescriptor> _dependencies;

    public AbpModuleDescriptor(
        [NotNull] Type type,
        [NotNull] IAbpModule instance,
        bool isLoadedAsPlugIn)
    {
        Check.NotNull(type, nameof(type));
        Check.NotNull(instance, nameof(instance));
        AbpModule.CheckAbpModuleType(type);

        if (!type.GetTypeInfo().IsAssignableFrom(instance.GetType()))
        {
            throw new ArgumentException($"Given module instance ({instance.GetType().AssemblyQualifiedName}) is not an instance of given module type: {type.AssemblyQualifiedName}");
        }

        Type = type;
        Assembly = type.Assembly;
        AllAssemblies = AbpModuleHelper.GetAllAssemblies(type);
        Instance = instance;
        IsLoadedAsPlugIn = isLoadedAsPlugIn;

        _dependencies = new List<IAbpModuleDescriptor>();
    }

    public void AddDependency(IAbpModuleDescriptor descriptor)
    {
        _dependencies.AddIfNotContains(descriptor);
    }

    public override string ToString()
    {

View on GitHub (pinned to 7ed43b1931)

Solutions

Ensure the instance and the Type come from the same assembly/version; reload the plugin after rebuild.
Pass instance.GetType() as the type argument when you are unsure.
Check that no two modules share a name and get reordered by the loader.
If you maintain a custom loader, re-run AbpModule.CheckAbpModuleType and the IsAssignableFrom guard before building the descriptor.

Example fix

// before
var descriptor = new AbpModuleDescriptor(typeof(WrongModule), instance, true);

// after
var descriptor = new AbpModuleDescriptor(instance.GetType(), instance, true);

Defensive patterns

Strategy: validation

Validate before calling

static bool InstanceMatchesType(Type type, IAbpModule instance)
    => type.IsAssignableFrom(instance.GetType());

if (!InstanceMatchesType(declaredType, instance))
    throw new InvalidOperationException("instance/type mismatch");

Type guard

static bool IsModuleOf(Type type, IAbpModule instance) => type.IsAssignableFrom(instance.GetType());

Try / catch

try { var d = new AbpModuleDescriptor(type, instance, true); }
catch (ArgumentException ex) { logger.LogError(ex, "Module descriptor mismatch"); }

Prevention

Pair instance and type from the same assembly/version.
Use instance.GetType() when unsure of the declared type.
Rebuild plugins after module renames.

When it happens

Trigger: Constructing new AbpModuleDescriptor(type, instance, isLoadedAsPlugIn) where instance.GetType() is not assignable to type (a mismatch between the registered module type and the live instance).

Common situations: Two modules with similar names confused during refactoring, a plugin instance loaded from a different assembly version than the declared Type, or a hand-rolled module loader that pairs the wrong type+instance.

Related errors

AI-assisted analysis of abpframework/abp@7ed43b1931 (2026-08-13). Data as JSON: /api/errors/306037d84a0cb382. Report an issue: GitHub.