What causes a TypeLoadException on Migrate.exe for EF6?
entity-framework, entity-framework-migrations, sql-server
Solution
I just ran into this today. This can happen when you used the wrong sets of DLL when you run migrate.exe.
In my case, I used the .Net 4.5 version in migrate.exe but compiled my project using .Net 4.0's version.
After changing the dlls the problem went away.
Problem
I'm trying to run EF's migrate.exe from the command line as part of our build process. This is my actual command: ``` migrate.exe Hydrogen.Data.dll /startupConfigurationFile:..\..\..\Hydrogen.Web\Web.config /verbose ``` And it continually throws this exception: ``` System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.TypeInitializationException: The type initializer for 'System.Data.Entity.SqlServer.SqlProviderServices' threw an exception. ---> System.TypeLoadException: Method 'ExecuteAsync' in type 'System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy' from assembly 'EntityFramework.SqlServer, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' does not have an implementation. at System.Data.Entity.SqlServer.SqlProviderServices..ctor() at System.Data.Entity.SqlServer.SqlProviderServices..cctor() --- End of inner exception stack trace --- at System.Data.Entity.SqlServer.SqlProviderServices.get_Instance() --- End of inner exception stack trace --- at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor) at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments) at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture) at System.Reflection.RuntimePropertyInfo.GetValue(Object obj, Object[] index) at System.Data.Entity.Config.ProviderServicesFactory.GetInstance(Type providerType) at System.Data.Entity.Internal.AppConfig.<.ctor>b__2(ProviderElement e) at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext() at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source) at System.Data.Entity.Internal.AppConfig.<.ctor>b__1() at System.Lazy`1.CreateValue() at System.Lazy`1.LazyInitValue() at System.Data.Entity.Internal.AppConfig.get_DbProviderServices() at System.Data.Entity.Config.AppConfigDependencyResolver.RegisterDbProviderServices() at System.Data.Entity.Config.AppConfigDependencyResolver.GetServiceFactory(Type type, String name) at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory) at System.Data.Entity.Config.AppConfigDependencyResolver.GetService(Type type, Object key) at System.Linq.Enumerable.WhereSelectArrayIterator`2.MoveNext() at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source, Func`2 predicate) at System.Data.Entity.Config.CompositeResolver`2.GetService(Type type, Object key) at System.Data.Entity.Config.IDbDependencyResolverExtensions.GetService[T](IDbDependencyResolver resolver, Object key) at System.Data.Entity.DbContext.InitializeLazyInternalContext(IInternalConnection internalConnection, DbCompiledModel model) at Hydrogen.Data.HydrogenData..ctor() in c:\code\Hydrogen\Hydrogen.Data\HydrogenData.cs:line 18 --- End of inner exception stack trace --- at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck) at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) at System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) at System.Activator.CreateInstance(Type type, Boolean nonPublic) at System.Activator.CreateInstance(Type type) at System.Data.Entity.Infrastructure.DbContextInfo.<CreateActivator>b__2() at System.Data.Entity.Infrastructure.DbContextInfo..ctor(Type contextType, DbProviderInfo modelProviderInfo, AppConfig config, DbConnectionInfo connectionInfo) at System.Data.Entity.Infrastructure.DbContextInfo..ctor(Type contextType, DbConnectionInfo connectionInfo) at System.Data.Entity.Migrations.DbMigrator..ctor(DbMigrationsConfiguration configuration, DbContext usersContext) at System.Data.Entity.Migrations.DbMigrator..ctor(DbMigrationsConfiguration configuration) at System.Data.Entity.Migrations.Design.ToolingFacade.UpdateRunner.Run() at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate) at System.Data.Entity.Migrations.Console.Program.Run() at System.Data.Entity.Migrations.Console.Program.Main(String[] args) ERROR: Exception has been thrown by the target of an invocation. ``` When I run `Update-Database` from within Visual Studio everything works fine, so I know the migrations themselves are working. This is on a SQL Server database.