EF4 The provider did not return a Provider Manifest Token string - entity-framework

Question

Yes, one more question about Provider manifest token. Unfortunately all previous 22 questions was not useful to solve my problem. I developing simple web application using MVC4 + Code First + Sql Express.
Here is my context descendant:
public class MCQContext : DbContext
{
public MCQContext()
: base("name=ApplicationConnection")
{
}
...............
}
And here - part of web.config related to the problem:
<configuration>
<configSections>
<section name="entityFramework"
type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=4.4.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
requirePermission="false" />
</configSections>
<connectionStrings>
<add name="ApplicationConnection"
connectionString="Data Source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|aspnetdb.mdf;User Instance=true"
providerName="System.Data.SqlClient" />
</connectionStrings>
<entityFramework>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework">
<parameters>
<parameter value="name=ApplicationConnection" />
</parameters>
</defaultConnectionFactory>
</entityFramework>
So, as you can see, correct connection string passed to base of context class (I got the same error if I rename connection string to "MCQContext" and do not pass anything to parent context class).
I have no idea how to fix it. This behavior reproduced if I creating absolutely empty MVC4 application, remove all packages (I prefer manually specify required assemblies and do not use NuGet) and fix references (including reference to sqlserver express).

Answer 1

The problem with your connection string here is:
<add name="TrempimModel"
connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;
AttachDBFilename=|DataDirectory|aspnetdb.sdf;
User Instance=true"
providerName="System.Data.SqlClient" />
You're basically defining what "server" you're connecting to - but you're not saying what database inside the file to connect to. Also - the file extension for SQL Server Express database files is .mdf (not .sdf - that's SQL Server Compact Edition) - you need to take that into account, too! (was a typo, according to comment by OP).
You need to define an extra database=.... (or Initial Catalog=.....) in your connection string:
<add name="TrempimModel"
connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;
database=YourDatabaseName;
AttachDBFilename=|DataDirectory|aspnetdb.mdf;
User Instance=true"
providerName="System.Data.SqlClient" />
Then it should work just fine.