Hi. I'm trying to work through the sample programs in the book and ran into this error when trying to connect to the NORTHWND.mdf db:

System.Data.SqlClient.SqlException was unhandled
Message="A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)"

I'm pretty sure that means it can't open the database however I'm not sure what exactly I've done wrong. Any suggestions to get me jump started here?

This is my code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Data.Linq;
using System.Data.Linq.Mapping;
using System.Text;

namespace HelloLinqToSql
class HelloLinqToSql
[Table(Name = "Contacts")]
class Contact
public int ContactID {get; set;}
public string Name {get; set;}
public string City {get; set;}

static void Main(string[] args)
string cxn = @"C:workProjectsLinqInActionDataNORTHWND.mdf";
DataContext db = new DataContext(cxn);

var contacts =
from contact in db.GetTable<Contact>()
where contact.City == "Paris"
select contact;

foreach (var contact in contacts)
Console.WriteLine("Hello " + contact.Name);