Not able to connect SQL databse

using System;

using System.Collections.Generic;

using System.Text;

using System.Data;

using System.Data.SqlClient;

using System.Windows.Forms;

using System.IO;

//using System.ServiceProcess;

//using Microsoft.SqlServer.Management.Common;

//using Microsoft.SqlServer.Management.Smo;

using System.Diagnostics;

using System.Threading;

using ENTITY;

using System.Configuration;

//

//Summary description for DBConnection

//

namespace OpenMiracle.DAL

{

public class DBConnection

{

public SqlConnection sqlcon;

string strServer = ".\\MSSQLSERVER";

public string path = string.Empty;

public DBConnection()

{

/* */

//-------------Single User----------------------//

strServer = ".\\MSSQLSERVER";

if (File.Exists(Application.StartupPath + "\\sys.txt"))

{

strServer = File.ReadAllText(Application.StartupPath + "\\sys.txt"); // getting ip of server

}

if (PublicVariables._decCurrentCompanyId > 0)

{

path = Application.StartupPath + "\\Data\\" + PublicVariables._decCurrentCompanyId + "\\DBOpenMiracle.mdf";

}

else if (PublicVariables._decCurrentCompanyId == 0)

{

path = Application.StartupPath + "\\Data\\DBOpenMiracle.mdf";

}

else

{

path = Application.StartupPath + "\\Data\\COMP\\DBOpenMiracle.mdf";

}

sqlcon = new SqlConnection(@"Data Source=" + strServer + ";AttachDbFilename=" + path + ";Integrated Security=True;Connect Timeout=120;User Instance=True");

//;Max Pool Size=200

/*

sqlcon = new SqlConnection(@"Data Source=192.168.2.112\SQLS2008;database=DBOpenMiracle;user id='open';password='miracle';Connect Timeout=30;");

//----------------Server----------------------//

*/

///

/// SQL Express may take time to start up due to AutoClose Behaviour of SQLEXPRESS

/// Here we checking the sql connection and catches the logon error.

///

try

{

if (sqlcon.State == ConnectionState.Closed)

{

sqlcon.Open();

}

}

catch (SqlException sEx)

{

int i = sEx.Number;

if (i == 233)

{

Reconnect();

}

else if (i == -1)

{

MessageBox.Show("OpenMiracle","SQL connection failure... Please check the instance name of your sqlexpress with " + Application.StartupPath + " \\sys.txt");

}

else if (i == 18493)

{

ChangeConnectionForServer();

}

else

{

MessageBox.Show("Could not connect to your database... Please check your SQL Configuration", "OpenMiracle");

}

}

catch (Exception)

{

//Catche any other exception

}

finally

{

}

try

{

PrintWorks.frmDBConnection.connectionString = sqlcon.ConnectionString;

}

catch

{

//sql Error

}

}

///

/// SQL Express may take time to start up due to AutoClose Behaviour of SQLEXPRESS

///

///

private void Reconnect()

{

try

{

Thread.Sleep(30000);

if (sqlcon.State == ConnectionState.Closed)

{

sqlcon.Open();

}

}

catch (Exception)

{

MessageBox.Show("Your SQL Server is starting up... Please close and re-open the application", "OpenMiracle");

}

}

///

/// Cheanges the connection string to support SQLServer version instead of SQLExpress

///

private void ChangeConnectionForServer()

{

sqlcon = new SqlConnection(@"Data Source=" + strServer + ";AttachDbFilename=" + path + ";Integrated Security=True;Connect Timeout=120;User Instance=True");

}

}

}