Could not load file or assembly 'EntityFramework.SqlServer, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'

Question

I am using ASP.NET 5 and Entity Framework 6 (precisely 6.1.3), following this link. Tried every different solution like

Scrapping of Version in appconfig
Adding <dependentAssembly>
Reinstalling EntityFramework 6 again using Update-Package -reinstall EntityFramework
Check EntityFramwork.SqlServer
Cleared %temp% and did clean build along with standalone rebuild

I get error here

[DbConfigurationType(typeof(CodeConfig))]    
public class MyContext : DbContext
{
public MyContext()
        : base("DefaultConnection") <-- error here
    {
    }
 }

But still couldn't resolve this error, any helpful links would be appreciated

Could not load file or assembly 'EntityFramework.SqlServer, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies. The system cannot find the file specified.":"EntityFramework.SqlServer, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"

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.Data.Entity.Utilities.TypeExtensions.CreateInstance[T](Type type, Func`2 exceptionFactory)
   at System.Data.Entity.Utilities.TypeExtensions.CreateInstance[T](Type type, Func`3 typeMessageFactory, Func`2 exceptionFactory)
   at System.Data.Entity.Infrastructure.DependencyResolution.DbConfigurationManager.<.ctor>b__1()
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at System.Lazy`1.get_Value()
   at System.Data.Entity.Infrastructure.DependencyResolution.DbConfigurationManager.GetConfiguration()
   at System.Data.Entity.Infrastructure.DependencyResolution.InternalConfiguration.get_Instance()
   at System.Data.Entity.DbConfiguration.get_DependencyResolver()
   at System.Data.Entity.DbContext.InitializeLazyInternalContext(IInternalConnection internalConnection, DbCompiledModel model)
   at System.Data.Entity.DbContext..ctor(String nameOrConnectionString)
   at myproject.data.myprojectContext..ctor() in D:\Projects\Personal\myproject\myproject.data\myprojectContext.cs:line 12
   at myproject.data.Infrastructure.DatabaseFactory.Get() in D:\Projects\Personal\myproject\myproject.data\Infrastructure\DatabaseFactory.cs:line 9
   at myproject.data.Repository`1.get_DataContext() in D:\Projects\Personal\myproject\myproject.data\Repository.cs:line 28
   at myproject.data.Repository`1..ctor(IDatabaseFactory databaseFactory) in D:\Projects\Personal\myproject\myproject.data\Repository.cs:line 21
   at myproject.data.Repository.ProfileRepository..ctor(IDatabaseFactory databaseFactory) in D:\Projects\Personal\myproject\myproject.data\Repository\ProfileRepository.cs:line 9

Web.Config

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework.SqlServer, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
  </configSections>
  <connectionStrings>
    <add name="DefaultConnection" providerName="System.Data.SqlClient" connectionString="...." />
  </connectionStrings>
  <entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
      <parameters>
        <parameter value="mssqllocaldb" />
      </parameters>
    </defaultConnectionFactory>
    <providers>
      <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
    </providers>
  </entityFramework>
</configuration>

Could you try cleaning temporary files normally under C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files and Clean Solution? — Win
Also, try right click solution → clean solution → and rebuild And also something I have encountered before was that multiple entries of the public key token had been added to my app.config when I had this error. Strange isn't it — Eon
The worst case could you remove it completely, and install again instead of reinstall? — Win
@brykneval Whats your directory structure and where is the EntityFramework.SqlServer.dll? — CathalMF

Reishabh Reishabh · Accepted Answer · 2016-05-25T12:27:57

First check which version EF you are using. Check the your version. If you want to upgrade your version you can manage EF upgrade from NuGet.

Go to your Project solution - > 'Manage NuGet packet for Solution', click 'Manage' on 'Entity Framework'.

Now, Check your app.config . Maybe here wrong version number. The name="entityFramework" should have the correct version number.

Other then this, you should try installing the nuget package for EntityFramework.SqlServer by using following command in package manager console.

Install-Package EntityFramework.SqlServer -Version 7.0.0-beta6 -Pre

Could not load file or assembly 'EntityFramework.SqlServer, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'

1 Answers