Private Sub Workbook_Activate()
    MsgBox "1"
End Sub

Private Sub Workbook_WindowActivate(ByVal Wn As Window)
    MsgBox "2"
End Sub

Public WithEvents appevent As Application
Private Sub appevent_ProtectedViewWindowActivate(ByVal Pvw As ProtectedViewWindow)
    MsgBox "1"
End Sub

Private Sub appevent_ProtectedViewWindowOpen(ByVal Pvw As ProtectedViewWindow)
    MsgBox "2"
End Sub

Private Sub appevent_WindowActivate(ByVal Wb As Workbook, ByVal Wn As Window)
    MsgBox "3"
End Sub

Private Sub appevent_WorkbookActivate(ByVal Wb As Workbook)
    MsgBox "4"
End Sub

Private Sub appevent_WorkbookDeactivate(ByVal Wb As Workbook)
    MsgBox "5"
End Sub

Public WithEvents appevent As Application
Dim ret As String
Private Sub appevent_WorkbookActivate(ByVal wb As Workbook)

    Call ToggleDragAndDrop(wb, ret)
    'Comment out this line when satisfied it is working as expected
    MsgBox "Cell drag & drop enabled = " & ret
End Sub

Option Explicit
Public XLEvents As New cEventClass
Sub SetEventHandler()

If XLEvents.appevent Is Nothing Then
    Set XLEvents.appevent = Application
End If

End Sub

Sub ToggleDragAndDrop(wb As Workbook, Optional ret$)

    Application.CellDragAndDrop = (wb.Name <> ThisWorkbook.Name)
    ret = Application.CellDragAndDrop
End Sub

Option Explicit
Private Sub Workbook_Open()
    'Create the event handler when the workbook opens
    Call mod_DragDrop.SetEventHandler
    Call mod_DragDrop.ToggleDragAndDrop(Me)

End Sub

Private Sub Workbook_SheetActivate(ByVal Sh As Object)
' Additional safeguard in case state loss has killed the event handler:
' use some workbook-level events to re-instantiate the event handler

    Call Workbook_Open
End Sub

Private Sub Workbook_Open()
    'MsgBox "Opened and disabled"
    Application.CellDragAndDrop = False
End Sub

Private Sub Workbook_WindowActivate(ByVal Wn As Excel.Window)
    'MsgBox "Activated and disabled"
    Application.CellDragAndDrop = False
End Sub

Private Sub Workbook_WindowDeactivate(ByVal Wn As Excel.Window)
    'MsgBox "Deactivated and enabled"
    Application.CellDragAndDrop = True
End Sub

Private Sub Workbook_Before_Close(Cancel As Boolean)
    'MsgBox "Closed and enabled"
    Application.CellDragAndDrop = True
End Sub