Connection error while performing query

I'm a beginner in programming and I'm trying to connect to a database. But when I click the "Search" button to browse the database and display values on my screen, the following error is generated through a messagebox that I put in Catch:

  

"" An attempt to attach an auto-named database to C: \   database file). A database with the same name exists, or   specified file can not be opened, or it is located on UNC share. ""

Below is my code for connecting and displaying values:

namespace trenodb
{
    public partial class Form1 : Form
    {
        static string strDb = "Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=\"C:\Users\aRtHuRz\Documents\Visual Studio 2015\Projects\trenodb\trenodb\dbTrenodb.mdf\";Integrated Security=True;Connect Timeout=30";

    public Form1()
    {
        InitializeComponent();
    }

    private void btnPesquisar_Click(object sender, EventArgs e)
    {
        string pesquisar = "SELECT * FROM Table WHERE [Id] = " + txtID;
        SqlConnection conexao = new SqlConnection(strDb);
        SqlCommand cmd = new SqlCommand(pesquisar, conexao);
        SqlDataReader DR;
        try
        {
            conexao.Open();
            DR = cmd.ExecuteReader();
            if (DR.Read())
            {
                txtID.Text = DR.GetValue(0).ToString();
                txtNome.Text = DR.GetValue(1).ToString();
                txtFone.Text = DR.GetValue(2).ToString();
                txtEndereço.Text = DR.GetValue(3).ToString();
                DR.Close();
            } cmd.Dispose();
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
        finally
        {
            conexao.Close();
        }
    }
}

}