Question

Error:

Could not load System.Data.SqlServerCe.Entity.dll. Reinstall SQL Server Compact.

Inner Exception:

{"Could not load file or assembly 'System.Data.SqlServerCe.Entity, Version=4.0.0.1, Culture=neutral, PublicKeyToken=89845dcd8080cc91' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)":"System.Data.SqlServerCe.Entity, Version=4.0.0.1, Culture=neutral, PublicKeyToken=89845dcd8080cc91"}

Steps to Reproduce:

1. Create new MVC3 Application

2. Add Nuget Package EntityFramework.SqlServerCompact

   <package id="EntityFramework.SqlServerCompact" version="4.1.8482.2" />

3. Create Model

   public class TaskItem
   {
       [Key]
       public int Id { get; set; }
       public string Description { get; set; }
   }
   

4. Create DbContext

   public class TestContext : DbContext
   {
       public DbSet<TaskItem> TaskItems { get; set; }
   }
   

5. Home Controller

   public ActionResult Index()
   {
       var db = new TestContext();
       // breakpoint on Add() below
       db.TaskItems.Add(new TaskItem { Description = "Get shit done."});
       return View();
   }
   

6. Web.config Connection String and Runtime and System.Data

   <add name="ApplicationServices" connectionString="Data Source=|DataDirectory|Test.sdf" providerName="System.Data.SqlServerCe.4.0" />

   <runtime>
       <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
         <dependentAssembly>
           <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
           <bindingRedirect oldVersion="1.0.0.0-2.0.0.0" newVersion="3.0.0.0" />
         </dependentAssembly>
         <dependentAssembly>
           <assemblyIdentity name="System.Data.SqlServerCe" publicKeyToken="89845dcd8080cc91" culture="neutral" />
           <bindingRedirect oldVersion="0.0.0.0-4.0.0.1" newVersion="4.0.0.1" />
         </dependentAssembly>
       </assemblyBinding>
     </runtime>
     <system.data>
       <DbProviderFactories>
         <remove invariant="System.Data.SqlServerCe.4.0" />
         <add name="Microsoft SQL Server Compact Data Provider 4.0" invariant="System.Data.SqlServerCe.4.0" description=".NET Framework Data Provider for Microsoft SQL Server Compact" type="System.Data.SqlServerCe.SqlCeProviderFactory, System.Data.SqlServerCe, Version=4.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" />
       </DbProviderFactories>
     </system.data>
   

Question:

Web.config is all default… nothing funky here… all the DLLs are copy local and in bin… what am I missing? It’s got to be something very simple.

---

Update:

Removing the Dependent Assembly section from web.config solved the problem, but I still need an explanation why in order to close the answer.

Answer 1

Remove the dependent assembly binding from your web.config

  <dependentAssembly>
    <assemblyIdentity name="System.Data.SqlServerCe" publicKeyToken="89845dcd8080cc91" culture="neutral" />
    <bindingRedirect oldVersion="0.0.0.0-4.0.0.1" newVersion="4.0.0.1" />
  </dependentAssembly>