Named Pipes Error

I'm working on an insert into a database and I barrowed this code stright from Microsoft, changing the info I need. I keep getting an error "An error has occurred while establishing a connection to the server.  When connecting to SQL Server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)" This is the same connection string that I use for querying the database without a problem. Anyone have any ideas?

Jeff

SqlConnection con = new SqlConnection("Data Source=.SQLEXPRESS;AttachDbFilename=software.mdf;Integrated Security=True;User Instance=True;");
SqlCommand cmd = new SqlCommand("INSERT INTO download_table (username, computer_name, computer type, install type, date, email, agree, title) VALUES (@username, @computer_name, @comptype, @installtype, @date, @email, @agree, @title)", con);
cmd.Parameters.Add(new SqlParameter("@username", SqlDbType.VarChar, 50));
cmd.Parameters["@username"].Value = username;
cmd.Parameters.Add(new SqlParameter("@computer_name", SqlDbType.VarChar, 50));
cmd.Parameters["@computer_name"].Value = computer_name;
cmd.Parameters.Add(new SqlParameter("@comptype", SqlDbType.VarChar, 50));
cmd.Parameters["@comptype"].Value = comptype;
cmd.Parameters.Add(new SqlParameter("@installtype", SqlDbType.VarChar, 50));
cmd.Parameters["@installtype"].Value = installtype;
cmd.Parameters.Add(new SqlParameter("@date", SqlDbType.DateTime, 50));
cmd.Parameters["@date"].Value = date;
cmd.Parameters.Add(new SqlParameter("@email", SqlDbType.VarChar, 50));
cmd.Parameters["@email"].Value = email;
cmd.Parameters.Add(new SqlParameter("@agree", SqlDbType.VarChar, 50));
cmd.Parameters["@agree"].Value = agree;
cmd.Parameters.Add(new SqlParameter("@title", SqlDbType.VarChar, 50));
cmd.Parameters["@title"].Value = title;
cmd.Connection.Open(); <--- This is where I get the above error
try
{
cmd.ExecuteNonQuery();
}
catch (SqlException ex)
{
}
cmd.Connection.Close();