CrystalReport Error

Question

OracleCommand cmd = new OracleCommand(qry, db.Con);

OracleDataAdapter da = new OracleDataAdapter(cmd);

DataSet ds = new DataSet();

da.Fill(ds);

ReportDocument Report = new ReportDocument();

Report.Load(Server.MapPath("~/Reports/Example.rpt"));

Report.SetDataSource(ds);

Report.SetParameterValue("Company", AppSettings.Company);

Report.SetParameterValue("Add1", AppSettings.Add1);

Report.SetParameterValue("Add2", AppSettings.Add2);

CrystalReportViewer1.ReportSource = auditReport;

CrystalReportViewer1.DataBind();

 

 

Error Message:

 

Error

Failed to open the connection. Details: [Database Vendor Code: 12154 ]

 

Please Clarify With Detail Coding because I am new in Crystal Report.