Crystal reports "database logon failed"error?

using CrystalDecisions.CrystalReports.Engine;
using CrystalDecisions.Shared;

// create the report object
ReportDocument rptDoc = new ReportDocument();
rptDoc.Load("<Path & file name of the report>");
// create the connection information
ConnectionInfo conRpt = new ConnectionInfor();
conRpt.ServerName = "DB Server Name";
conRpt.DatabaseName = "DB Name";
conRpt.UserID = "User name";
conRpt.Password = "Password";
// apply connection information to the report tables
Tables rptTables = rptDoc.Database.Tables;
for(int i = 0; i < rptTables.Count; i++)
{
    Table rptTable = rptTables[i];
    TableLogOnInfo tblInfo = rptTable.LogOnInfo;
    tblInfo.ConnectionInfo = conRpt;
    // next table
}
// if the report contains sub reports, you will need to set the connection info there too
if(rptDoc.SubReports.Count > 0)
{
    for(int i = 0; i < rptDoc.Subreports.Count; i++)
    {
        using(ReportDocument rptSub = rptDoc.OpenSubReport(rptDoc.SubReports[i].Name))
        {
            Tables rptTables = rptSub.Database.Tables;
            for(int i = 0; i < rptTables.Count; i++)
            {
                Table rptTable = rptTables[i];
                TableLogOnInfo tblInfo = rptTable.LogOnInfo;
                tblInfo.ConnectionInfo = conRpt;
                // next table
            }
            rptSub.Close();
        }
    }
}
// Show Report in Viewer - you can also send direct to a printer if required
// Note; do not call refresh report on the ReportViewer control as this will undo all of the above
frmReportViewer.ReportSource = rptDoc;