'The underlying Provider failed on Open' C# ASP.net

Question

I have an application that has 4 layers, which are the following : Dominio, Infra, Servico, Web in the domain I have a folder called Poco with all my Classes/Tabelas , in the Layer Infra, to test the CodeFirst I believed an object and gave Servico.Add(Obejto) to save in the bank , but when trying to access the bank I got the following error back :

'The underlying provider failed on Open'

and within that exceptio I have another that says the following :

"Instance-specific or network error when connecting to SQL Server. The server was not found or not accessible. Check that the instance name is correct and that SQL Server is configured to allow remote connections. (Preview: Named Pipes Provider, error: 40 - Unable to open SQL connection Server)

And there’s one more :

"The network path was not found"

My string conection that is called Contexto in Server Explorer shows how open connection.

<add name="Contexto" connectionString="DataSource=494.sqlserver.sequelizer.com;
Initial Catalog=db49c6a5011d0751;
Persist Security Info=True;
User ID="*";Password="*";MultipleActiveResultSets=True" providerName="System.Data.SqlClient

The Server data has been changed for security, I am using an instance of appHarbor that is empty anyway, if you need to post the data kingas .

I have my own Contexto that it is declared as follows::

 public class Contexto : DbContext, IDisposable
{ 
   //Essas são apenas algumas das Classes/Tabelas 

    public DbSet<AdministradorUnidade> AdministradorUnidade { get; set; }
    public DbSet<Pessoa> Pessoa { get; set; }
    public DbSet<Categoria> Categoria { get; set; }
    public DbSet<CategoriaEspecialidade> CategoriaEspecialidade { get; set;}
    public DbSet<CategoriaTratamento> CategoriaTratamento { get; set; }
    public DbSet<CategoriaVideoParceiro> CategoriaVideoParceiro { get; set;}
    public DbSet<CategoriaVideoServico> CategoriaVideoServico { get; set; }
    public DbSet<Cidade> Cidade { get; set; }



    public virtual void Commit()
    {
        base.SaveChanges();
    }

    public new void Dispose()
    {
        base.Dispose();
    }


}

I also have in that folder DataBaseFactory and UnitOfWork(If necessary I put these too)

My Connection string with the database is correct View -> Server Explorer and put the connection this made open, but still I still try this problem.