title: Entity Framework : "The underlying provider failed on Open"
body: <p>When I try to insert a record, I get this error : The underlying provider failed on Open.
  This error occurs only with IIS and not with VWD 2008's webserver. 
  In the EventViewer I get this Application Error : <strong>Failed to generate a user instance of SQL Server due to a failure in starting the process for the user instance. The connection will be closed. [CLIENT: ]</strong></p>
  
  <pre><code>&lt;add name="ASPNETDBEntities"
       connectionString="
           metadata=res://*/Models.FriendList.csdl|res://*/Models.FriendList.ssdl|res://*/Models.FriendList.msl;
           provider=System.Data.SqlClient;
           provider connection string=&amp;quot;
           Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\ASPNETDB.MDF;
           Integrated Security=True;
           Connect Timeout=30;
           User Instance=True;
           MultipleActiveResultSets=True&amp;quot;"
       providerName="System.Data.EntityClient" /&gt;
  </code></pre>
  
  <p><strong>I am using aspnetdb.mdf file, and not any external database.</strong>
  I have searched enough for this, but no use.</p>
  
  <p><strong>Everything works fine with VWD webserver</strong></p>