Time out expired probleme sometime

Question

I use C#, .NET Framework 4.0 and SQL Server 2008 R2 Express, and I wrote a Winforms program with it.

I got this message:

The timeout period elapsed prior to completion of the operation or the server is not responding.

I searched it and found some hint, like

hint 1

Facts:

• I did close my database connection
• I have set the timeout = 0
• I did apply the corrective framework microsoft correctif framework

Here is my connection class (Data Layer):

class Connexion : IDisposable 
{
        public SqlConnection conn;

        public SqlConnection GetConnected()
        {
            try
            {
                //String strConnectionString = ConfigurationManager.ConnectionStrings["Soft8Exp_ClientConnStr"].ConnectionString;
                string strConnectionString = Properties.Settings.Default.Soft8Exp_ClientConnStr;
                conn = new SqlConnection(strConnectionString);
            }
            catch (Exception excThrown)
            {
                conn = null;
                throw new Exception(excThrown.InnerException.Message, excThrown);
            }

            // Ouverture et restitution de la connexion en cours
            if (conn.State == ConnectionState.Closed) conn.Open();
            return conn;
        }

        public Boolean IsConnected
        {
            get { return (conn != null) && (conn.State != ConnectionState.Closed) && (conn.State != ConnectionState.Broken); }
        }

        public void CloseConnection()
        {
            // Libération de la connexion si elle existe
            if (IsConnected)
            {
                conn.Close();
                conn = null;
            }
        }

        public void Dispose()
        {
            CloseConnection();
        }
}

and I use it like this (Business Layer):

public string Cloturer_Ordre_Unitaire_Agence(string CHAUFFEUR, string ClotList, DateTime Enlev, DateTime ClotReel, string sql_Syntax, string Unitaire, string NomAgence)
{
            try
            {
                using (var connectionWrapper = new Connexion())
                {
                    var connectedConnection = connectionWrapper.GetConnected();

                    SqlCommand comm_Command = new SqlCommand(sql_Syntax, connectionWrapper.conn);
                    comm_Command.CommandTimeout = 0;
                    comm_Command.Parameters.AddWithValue("@CHAUFFEUR", CHAUFFEUR);
                    comm_Command.Parameters.AddWithValue("@Trans", ClotList);
                    comm_Command.Parameters.AddWithValue("@DATE_CLOTUR_REEL", ClotReel);
                    comm_Command.Parameters.AddWithValue("@DateEnlev", Enlev);
                    comm_Command.Parameters.AddWithValue("@Unitaire", Unitaire);
                    comm_Command.Parameters.AddWithValue("@AGENCE", NomAgence);
                    string IdOrdre = "";
                    SqlDataReader readerOne = comm_Command.ExecuteReader();

                    while (readerOne.Read())
                    {
                        if (IdOrdre != "") IdOrdre += ",";
                        IdOrdre += readerOne["NO_ORDRE"].ToString();
                    }

                    return IdOrdre;
                }
            }
            catch (Exception excThrown)
            {
                throw new Exception(excThrown.Message);
            }
}

but after all I did, why do I still SOMETIMES get a timeout problem?

Do I have to:

• delete the .ldf file because it to big
• index my table
• tune my SQL syntax

should i tune this sql:

DECLARE @AfterUpdate table (
    NO_ORDRE_Temp int NOT NULL, 
    CODE_DEST_Temp varchar(50) NOT NULL,
    DATE_CLOTUR_Temp datetime NOT NULL, 
    FA_CLIENT_Temp varchar(20) NOT NULL,
    CODE_CLIENT_Temp varchar(20) NOT NULL,
    MODAL_MODE_Temp char(1) NOT NULL,
    MODAL_PORT_Temp bit NOT NULL,
    LIVRS_EXPRS_Temp bit NOT NULL,
    ENLEV_UNITE_Temp int NOT NULL,
    NBR_COLIS_Temp int NOT NULL,
    POID_Temp decimal(10, 2) NOT NULL,
    ENLEV_CREMB_Temp decimal(10, 2)  NULL,
    ENLEV_DECL_Temp decimal(10, 2)  NULL,
    TRANSPORTEUR_Temp varchar(5) NOT NULL,
    CODE_MAG_Temp varchar(50) NOT NULL,
    FACTURATION_Temp int NOT NULL,
    LIVRS_SIGN_Temp bit NOT NULL,
    LIVRS_SAMD_Temp bit NOT NULL,
    OBS_Temp varchar(max) NOT NULL,
    AGENCE_Temp varchar(max) NOT NULL,
    LIB_TOURNE_Temp varchar(50) NOT NULL,
    DATE_CLOTUR_REEL_Temp datetime NOT NULL,
    ADRESSE_Temp varchar(500) NOT NULL,
    REF_EXPED_Temp varchar(20) NOT NULL
  )  

UPDATE ORDRE 
SET STATUT_ORDRE = 2,  CHAUFFEUR = @CHAUFFEUR, FACTURATION= @CHAUFFEUR, DATE_CLOTUR_REEL = @DATE_CLOTUR_REEL
OUTPUT inserted.NO_ORDRE, inserted.CODE_DEST, inserted.DATE_CLOTUR, inserted.FA_CLIENT, inserted.CODE_CLIENT, inserted.MODAL_MODE, inserted.MODAL_PORT,inserted.LIVRS_EXPRS,inserted.ENLEV_UNITE,  inserted.NBR_COLIS,inserted.POID,inserted.ENLEV_CREMB,inserted.ENLEV_DECL, inserted.TRANSPORTEUR, inserted.CODE_MAG, inserted.FACTURATION, inserted.LIVRS_SIGN, inserted.LIVRS_SAMD, inserted.OBS, inserted.AGENCE, inserted.LIB_TOURNE, inserted.DATE_CLOTUR_REEL, inserted.ADRESSE, inserted.REF_EXPED INTO @AfterUpdate
WHERE STATUT_ORDRE = 1 AND (TRANSPORTEUR IN (SELECT ParsedString From dbo.ParseStringList(@Trans))) 

INSERT INTO LETTRE_VOIT 

OUTPUT inserted.NO_ORDRE

select rsVoit.NOID, NO_ORDRE_Temp, rsOrdre.CODE_DEST_Temp,rsOrdre.DATE_CLOTUR_Temp,rsOrdre.FA_CLIENT_Temp, rsOrdre.CODE_CLIENT_Temp, rsOrdre.MODAL_MODE_Temp, rsOrdre.MODAL_PORT_Temp,
CASE rsOrdre.MODAL_PORT_Temp
            WHEN 'false' THEN N'Pay'+CHAR(233)
            ELSE 'Du'
        END, 
rsOrdre.LIVRS_EXPRS_Temp,
CASE rsOrdre.LIVRS_EXPRS_Temp
            WHEN 'false' THEN 'Express'
            ELSE 'Long'
        END, 
  rsOrdre.ENLEV_UNITE_Temp, LIBELLE, NBR_COLIS_Temp,POID_Temp,ENLEV_CREMB_Temp,ENLEV_DECL_Temp, TRANSPORTEUR_Temp, CODE_MAG_Temp, FACTURATION_Temp, LIVRS_SIGN_Temp, LIVRS_SAMD_Temp, OBS_Temp, AGENCE_Temp,LIB_TOURNE_Temp,DATE_CLOTUR_REEL_Temp,REF_EXPED_Temp
from @AfterUpdate rsOrdre
inner join
(
  select CODE_DEST,MODAL_MODE, MODAL_PORT, LIVRS_EXPRS,ENLEV_UNITE,AGENCE,CODE_CLIENT,ADRESSE, ROW_NUMBER() over (order by CODE_DEST) as NOID
  from ORDRE
  group by CODE_DEST,MODAL_MODE,MODAL_PORT,LIVRS_EXPRS,ENLEV_UNITE,AGENCE,CODE_CLIENT,ADRESSE
) rsVoit on rsVoit.CODE_DEST = rsOrdre.CODE_DEST_Temp and rsVoit.MODAL_MODE = rsOrdre.MODAL_MODE_Temp
and rsVoit.MODAL_PORT = rsOrdre.MODAL_PORT_Temp and rsVoit.LIVRS_EXPRS = rsOrdre.LIVRS_EXPRS_Temp
and rsVoit.ENLEV_UNITE = rsOrdre.ENLEV_UNITE_Temp and rsVoit.AGENCE = rsOrdre.AGENCE_Temp
 and rsVoit.CODE_CLIENT = rsOrdre.CODE_CLIENT_Temp and rsVoit.ADRESSE = rsOrdre.ADRESSE_Temp

LEFT JOIN T_UNITE ON rsOrdre.ENLEV_UNITE_Temp = T_UNITE.NOID


order by rsVoit.NOID, NO_ORDRE_Temp

another SQL:

SELECT *, 
--FAWEB_CLIENT.RS_NOM AS RS_NOM_EXP,
--FAWEB_CLIENT.ADRESSE AS ADDR_EXP,
--FAWEB_CLIENT.CP AS CP_EXP,
--FAWEB_CLIENT.VILLE AS VILLE_EXP,
--FAWEB_CLIENT.TEL AS TEL_EXP,
--FAWEB_CLIENT.FAX AS FAX_EXP,

AGENCE.NOM AS RS_NOM_EXP,
AGENCE.ADRESSE AS ADDR_EXP,
AGENCE.CP AS CP_EXP,
AGENCE.VILLE AS VILLE_EXP,
AGENCE.TELP AS TEL_EXP,
'' AS FAX_EXP,


ORDRE.RS_NOM AS RS_NOM_DEST,
ORDRE.ADRESSE AS ADDR_DEST,
ORDRE.CP AS CP_DEST,
ORDRE.INSEE AS INSEE_DEST,
ORDRE.VILLE AS VILLE_DEST,
ORDRE.TEL AS TEL_DEST,
ORDRE.FAX AS FAX_DEST

FROM LETTRE_VOIT 
LEFT JOIN AGENCE ON AGENCE.NOM = LETTRE_VOIT.LIB_AGENCE AND AGENCE.NO_CLIENT = LETTRE_VOIT.CODE_CLIENT
--LEFT JOIN FAWEB_CLIENT ON FAWEB_CLIENT.CODE_CLIENT = LETTRE_VOIT.CODE_CLIENT
LEFT JOIN ORDRE ON ORDRE.CODE_DEST = LETTRE_VOIT.CODE_DEST AND ORDRE.CODE_CLIENT = LETTRE_VOIT.CODE_CLIENT
           AND ORDRE.NO_ORDRE = LETTRE_VOIT.NO_ORDRE
WHERE  (LETTRE_VOIT.NO_ORDRE IN (SELECT ParsedString From dbo.ParseStringList(@Trans)))

--AND ORDRE.DATE_CLOTUR = LETTRE_VOIT.DATE_CLOTURE