MS Access DB produces run time error 2473 inconsistently - ms-access

Question

An Access DB I designed produces the run time error 2473 stating "Object or class does not support the set of events". The error is produced inconsistently, which makes it very hard for me to track it down.
The debugger stops on the following line of code when it appears:
'Open report containing code to create TOC with list of ISINs from above
DoCmd.OpenReport rptName, acViewPreview, , strWhere
Even when the error occurs, this code works fine for some reports, but produces the run time error for others. After opening up the report and the underlying queries in design mode, the run time error sometimes disappears, even though I have changed absolutely nothing in the code, the forms, or even updated the underlying data.
In an attempt to get at this problem, I have restored my DB to an earlier version where I know the problem still existed, but upon opening up the restored version, it no longer has a run time error either!
What could cause this behavior?
UPDATE:
Full code as contained in the Form
Sub cmdFundSelectionReport_Click()
'Gather selected ISIN and pass it to Fund Selection Report
Dim var As Variant
Dim sFund As String
Dim strWhere As String
Dim lst As Access.ListBox
Dim i As Integer
Dim rptType As Integer
'Create list of isin to send to report
Set lst = Me.libFilterSelection
rptType = Me.cmbReportType
Dim dict As Object
Set dict = CreateObject("Scripting.Dictionary")
For i = 0 To lst.ListCount - 1
If Not dict.Exists(lst.Column(1, i)) Then
dict.Add lst.Column(1, i), i
End If
Next i
Dim a As Variant
a = dict.keys
strWhere = "[ISIN] IN("
For i = 0 To dict.Count - 1
strWhere = strWhere & """" & a(i) & ""","
Next i
strWhere = Left(strWhere, Len(strWhere) - 1)
strWhere = strWhere & ")"
'Set dictionary back
Set dict = Nothing
Dim rptName As String
Select Case rptType
Case 2
rptName = "rptRDRSelectionList" '2 is the RDR List
'strWhere = strWhere & " AND Fund_Selection=2"
Case 3
rptName = "rptAsiaSelectionList" '3 Asia
'strWhere = strWhere & " AND Fund_Selection=3"
Case Else
rptName = "rptFundSelectionList" '0 = Fund Selection
'strWhere = strWhere & " AND Fund_Selection=0"
End Select
'Open Report for view
OpenReport rptName, strWhere
'Write Log
WritelogMessage Now & " | User: " & fncUserName & " | Report Created | ReportName: " & rptName
End Sub
Sub OpenReport(rptName As String, strWhere As String)
'Open report containing code to create TOC with list of ISINs from above
DoCmd.OpenReport rptName, acViewPreview, , strWhere
'Click through report so that TOC code is executed
Dim rptCurReport As Report
Set rptCurReport = Screen.ActiveReport
With rptCurReport
Application.DoCmd.SelectObject acReport, .Name
.Visible = True 'switch to false once code is ok
'Go through all pages
SendKeys "{End}", True
DoEvents
Application.DoCmd.SelectObject acReport, .Name
DoCmd.Close acReport, .Name, acSaveNo
End With
rptName = rptName & "TOC" 'Add TOC to get Table of Contents Report
''Check whether "Internal Use Only Flag" is set to true or false
'Dim bInternalUse As Boolean
'bInternalUse = Me.ckbInternalUse.Value
'Call modProcess.ChangeReportPicture("rptFundSelectionListTOC", "picInternalUse", bInternalUse)
'Open final report that includes the TOC as a subreport with same string of ISIN
DoCmd.OpenReport rptName, acViewPreview, , strWhere
SendKeys "{Home}", True
DoEvents
End Sub