Error de código al cargar un report !!!!!

Hola nuevamente

Cuando hago un debug de mi aplicación, luego del end sub de la rutina de
cargar el report me pone este error

there is no source code available for the current location..

Que es ? de que se trata ? el código es este

Imports CrystalDecisions.CrystalReports.Engine
Public Class FrmBalanResRpt
Inherits System.Windows.Forms.Form

Private ViewCarga As String
Protected WithEvents m_DAL As SGI.BalanRes
Dim crReportDocument As BalanResRpt
Private dsBalanRes As DataSet
Dim daBalanRes As Data.SqlClient.SqlDataAdapter
Private dtBalanRes As DataTable
Private dvBalanRes As DataView
Private Desde As String
Private Hasta As String

Private Sub CargaReport()
Try
Desde = DTPIssued.Value
Hasta = DtPCobro.Value

If m_DAL Is Nothing Then
m_DAL = New SGI.BalanRes
End If
dsBalanRes = m_DAL.CreateDataSet(Desde, Hasta)

Dim pvCollection As New CrystalDecisions.Shared.ParameterValues
Dim pvCol As New CrystalDecisions.Shared.ParameterValues
Dim pdvDesde As New
CrystalDecisions.Shared.ParameterDiscreteValue
Dim pdvHasta As New
CrystalDecisions.Shared.ParameterDiscreteValue

Dim crReportDocument As New ReportDocument
crReportDocument = New BalanResRpt
pdvDesde.Value = DTPIssued.Value
pdvHasta.Value = DtPCobro.Value

pvCollection.Add(pdvDesde)
pvCol.Add(pdvHasta)

crReportDocument.DataDefinition.ParameterFields("@desde").ApplyCurrentValues(pvCollection)
crReportDocument.DataDefinition.ParameterFields("@hasta").ApplyCurrentValues(pvCol)
crReportDocument.SetDataSource(dsBalanRes)
CRVBalanRes.ReportSource = crReportDocument

Catch exc As Exception
MsgBox(exc.Message, MsgBoxStyle.Critical, Me.Text)
End Try
End Sub

Private Sub UltraButton1_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles UltraButton1.Click
Try
If DtPCobro.Value < DTPIssued.Value Then
MsgBox("La fecha de comparación final es menor que la de
inicio", MsgBoxStyle.Exclamation, Me.Text)
Return
End If

CargaReport()
Catch exc As Exception
MsgBox(exc.Message, MsgBoxStyle.Critical, Me.Text)
End Try
End Sub
End Class