title: Error: No Entity Framework provider found for the ADO.NET provider with invariant name 'System.Data.SqlClient'
body: <p>I recently upgraded/updated Entity Framework in an old project from version 4 or 5 to version 6. Now I get this exception:</p>
  
  <blockquote>
    <p>An exception of type 'System.InvalidOperationException' occurred in
    EntityFramework.dll but was not handled in user code</p>
    
    <p>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
    <a href="http://go.microsoft.com/fwlink/?LinkId=260882">http://go.microsoft.com/fwlink/?LinkId=260882</a> for more information.</p>
  </blockquote>
  
  <p>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:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;configuration&gt;
    &lt;configSections&gt;
      &lt;!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 --&gt;
      &lt;section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" /&gt;
    &lt;/configSections&gt;
    &lt;entityFramework&gt;
      &lt;defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" /&gt;
      &lt;providers&gt;
        &lt;provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" /&gt;
      &lt;/providers&gt;
    &lt;/entityFramework&gt;
  &lt;/configuration&gt;
  </code></pre>
  
  <p>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.</p>