MDF dont connect in ASP NET

Question

I'm working in Visual Studio 2012 and trying to connect my website to an mdf database file (sisgar.mdf):

I have tried to connect with this code:

 @{
  var base_dados = Database.Open("sisgar");
  string query = ("select * from tb_porteiro");
   var resultados = base_dados.Query(query);

<table>
    @{
    foreach ( var linha in resultados )
    {
      <tr>
          <td>@linha.idp </td>
          <td>@linha.porteiro </td>
      </tr>
    }
    }

The mdf is in the right folder, the table exists, have the fields

Return this error

Exists another way to connect to the mdf

Answer 1

Solution

1. Open Task Manager and look for sqlsrv.exe process and end it

2. Delete all files in the

   %LOCALAPPDATA%\Microsoft\Microsoft SQL Server Data\SQLEXPRESS 
   

   folder

3. Then run again.

For more details, you can check the posts below:

1. Failed to generate a user instance of SQL Server due to a failure in starting the process for the user instance.

2. Error: Failed to generate a user instance of SQL Server

Workaround

If the solution not works for you. Please try to attach your mdf file to your sql server.