Crystal Reports in ASP.Net: Logon failed. Details: crdbadoplus : Object reference not set to an

Paste the code and let us know the line throwing error

Dim ReportDocument As New CrystalDecisions.CrystalReports.Engine.ReportDocument
        ReportDocument.Load(Server.MapPath("CrystalReport.rpt"))
        ReportDocument.SetDatabaseLogon("", "", "ali", "payroll")
        CrystalReportViewer1.ReportSource = ReportDocument
        CrystalReportViewer1.Visible = True

As per the error it means login has failed for the Database you are connecting to

Self mention correct details still it prompt error while running into browser. Can u pls guide me as how to create Crystal reports in asp.net and to view the same into PDF or EXL Format..

Refer

Crystal Reports: Unable to connect: incorrect log ...