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Error: No Entity Framework provider found for the ADO.NET provider with invariant name 'System.Data.SqlClient' (8)

Hendry's answer is 100% correct. I had the same problem with my application, where there is repository project dealing with database with use of methods encapsulating EF db context operation. Other projects use this repository, and I don't want to reference EF in those projects. Somehow I don't feel it's proper, I need EF only in repository project. Anyway, copying EntityFramework.SqlServer.dll to other project output directory solves the problem. To avoid problems, when you forget to copy this dll, you can change repository build directory. Go to repository project's properties, select Build tab, and in output section you can set output directory to other project's build directory. Sure, it's just workaround. Maybe the hack, mentioned in some placec, is better:

var instance = System.Data.Entity.SqlServer.SqlProviderServices.Instance;

Still, for development purposes it is enough. Later, when preparing install or publish, you can add this file to package.

I'm quite new to EF. Is there any better method to solve this issue? I don't like "hack" - it makes me feel that there is something that is "not secure".

I recently upgraded/updated Entity Framework in an old project from version 4 or 5 to version 6. Now I get this exception:

An exception of type 'System.InvalidOperationException' occurred in EntityFramework.dll but was not handled in user code

Additional information: No Entity Framework provider found for the ADO.NET provider with invariant name 'System.Data.SqlClient'. Make sure the provider is registered in the 'entityFramework' section of the application config file. See http://go.microsoft.com/fwlink/?LinkId=260882 for more information.

I googled the error and came across a couple of SO threads, but none of them contained a solution that works for me. This is what my App.config looks like:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
    <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
  </configSections>
  <entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
    <providers>
      <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
    </providers>
  </entityFramework>
</configuration>

I already uninstalled Entity Framework from my project and re-installed it, deleted all the references to old EF files and re-installed, but nothing works for me. I keep getting this error.


I also had a similar problem

My problem was solved by doing the following:


I had this problem in a situation where I have a model project that has the references to both EntityFramework and the .SqlServer assemblies, and a separate UI project that uses ASP.NET MVC. I wanted to upgrade from EF 4.1 to 6.1. I actually had to do part of what was described here: http://robsneuron.blogspot.com/2013/11/entity-framework-upgrade-to-6.html. I want to emphasize that I did not add a reference to these projects to my UI project nor did I add the configuration to the UI project's web.config, as those steps would violate my separation of concerns.

What I did do was in my model project, I had to flip the "Copy Local" reference settings for EntityFramework.SqlServer (and the EntityFramework reference, to be safe) to "False" and save all, to get the project to put the <Private> node into the .csproj file, and then set it back to "True" and save again, so that True ends up as the final value.

I also had to add the hack line to my DbContext-derived class in its constructor to force the use of the assembly, even though the line does nothing. Both of these steps I learned from the blog post.

public MyContext : DbContext
{
    public MyContext() : base("name=MyContext")
    {
        // the terrible hack
        var ensureDLLIsCopied = 
                System.Data.Entity.SqlServer.SqlProviderServices.Instance;   
    }

I want to thank the author of that blog that I referenced, as well as all the people that asked and answered the questions on SO, to try to help us get past this terrible bug.


I have solved the issue using below code in my DBContext

 
public partial class Q4Sandbox : DbContext
    {
        public Q4Sandbox()
            : base("name=Q4Sandbox")
        {
        }

        public virtual DbSet Employees { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {           
           var instance = System.Data.Entity.SqlServer.SqlProviderServices.Instance;
        }
    }

Thanks to a SO member.


I just solved it. You need to install Entity Framework again in your solution. Follow any of the approaches.

First = Right Click your Solution or Project root and click Manage NuGet Packages. Select 'EntityFramework', select the appropriate Projects and click Ok.

or

Second = Go to Console Package Manager and run Install-Package EntityFramework.

Hope it helps.


Ok, this is pretty weird. I have a couple of projects: one is a UI project (an ASP.NET MVC project) and the others are projects for stuff like repositories. The repositories project had a reference to EF, but the UI project didn't (because it didn't need one, it just needed to reference the other projects). After I installed EF for the UI project as well, everything started working. This is why, it added this piece of code to my Web.config:

<entityFramework>
  <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
  <providers>
    <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
  </providers>
</entityFramework>

Try adding the following runtime assembly bindings:

<runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="EntityFramework" publicKeyToken="b77a5c561934e089" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-6.0.0.0" newVersion="6.0.0.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>

What worked for me was downgrading from EF 6.1.3 to EF 6.1.1.

In Visual Studios 2012+ head over to:

Tools - Nuget Package Manager - Package Manager Console`

Then enter:

Install-Package EntityFramework.SqlServerCompact -Version 6.1.1

I did not have to uninstall EF 6.1.3 first because the command above already does that.

In addition, I don't know if it did something, but I also installed SQL Server CE in my project.

Here's the link to the solution I found:

http://www.itorian.com/2014/11/no-entity-framework-provider-found-for.html







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