Error running code first migration update-database

Question

Im having trouble with my migration to my database and i can't seem to find a answer to the error i am getting

 System.MissingMethodException: Method not found: 'System.Data.Entity.Migrations.Builders.TableBuilder`1 System.Data.Entity.Migrations.Builders.TableBuilder`1.Index(System.Linq.Expressions.Expression`1>, Boolean, Boolean, System.Object)'.
   at Evento.Migrations.initialcreate.Up()
   at System.Data.Entity.Migrations.DbMigrator.ApplyMigration(DbMigration migration, DbMigration lastMigration)
   at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.ApplyMigration(DbMigration migration, DbMigration lastMigration)
   at System.Data.Entity.Migrations.DbMigrator.Upgrade(IEnumerable`1 pendingMigrations, String targetMigrationId, String lastMigrationId)
   at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.Upgrade(IEnumerable`1 pendingMigrations, String targetMigrationId, String lastMigrationId)
   at System.Data.Entity.Migrations.DbMigrator.UpdateInternal(String targetMigration)
   at System.Data.Entity.Migrations.DbMigrator.c__DisplayClassc.b__b()
   at System.Data.Entity.Migrations.DbMigrator.EnsureDatabaseExists(Action mustSucceedToKeepDatabase)
   at System.Data.Entity.Migrations.Infrastructure.MigratorBase.EnsureDatabaseExists(Action mustSucceedToKeepDatabase)
   at System.Data.Entity.Migrations.DbMigrator.Update(String targetMigration)
   at System.Data.Entity.Migrations.Infrastructure.MigratorBase.Update(String targetMigration)
   at System.Data.Entity.Migrations.Design.ToolingFacade.UpdateRunner.Run()
   at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate)
   at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate)
   at System.Data.Entity.Migrations.Design.ToolingFacade.Run(BaseRunner runner)
   at System.Data.Entity.Migrations.Design.ToolingFacade.Update(String targetMigration, Boolean force)
   at System.Data.Entity.Migrations.UpdateDatabaseCommand.c__DisplayClass2.b__0()
   at System.Data.Entity.Migrations.MigrationsDomainCommand.Execute(Action command)
Method not found: 'System.Data.Entity.Migrations.Builders.TableBuilder`1 System.Data.Entity.Migrations.Builders.TableBuilder`1.Index(System.Linq.Expressions.Expression`1>, Boolean, Boolean, System.Object)'. 

Answer 1

I ran into this same issue and here is how I resolved it. I hope this helps someone else.

1. I deleted Entity Framework from my References and removed the lines from my package.config file(s).
2. Closed Visual Studio and deleted all the EntityFramework DLL files in my project folders
3. Opened Visual Studio, then did a Clean and Build
4. Re-install Entity Framework
5. Did a Clean and Build again

After that, it was working.

Answer 2

I ran into this error when running db.Database.Initialize(true);. I discovered that my the console app was referencing EF v 6.0, but the project with the DataContext and ModelBuilder were 6.1.3.

The error went away after setting the console app to 6.1.3 to match the others.