How to report progress here?

Public Function CollectFiles(ByVal dir As String, ByVal pattern As String) As List(Of FileInfo)

    Try
        Dim di As New DirectoryInfo(dir)
        Dim queue As New ConcurrentQueue(Of FileInfo)()
        InternalCollectFiles(di, pattern, queue)
        Return queue.AsEnumerable().ToList()

    Catch ex As Exception
        MsgBox(String.Format("Error in 'CollectFiles': {0}", ex.Message))
        Return Nothing

    End Try

End Function

Private Sub InternalCollectFiles(ByVal dir As DirectoryInfo, ByVal pattern As String, ByVal queue As ConcurrentQueue(Of FileInfo))

    If dir.FullName.Contains(My.Computer.Name) Then
        ' new directoryinfo, if single computer
        dir = New DirectoryInfo(Right(dir.FullName, 2).Replace("$", ":\"))
    End If

    Try
        For Each result As FileInfo In dir.GetFiles(pattern).Select(Function(file) file) _
         .Where(Function(s) supportedExtensions.Contains(Path.GetExtension(s.Extension).ToLower()))
            'Dim msg As String = String.Format("{0}", dir.FullName)
            'UIDelegate.Invoke(msg, "")
            queue.Enqueue(result)
        Next result
        Task.WaitAll(dir.GetDirectories().Select(Function(d) Task.Factory.StartNew(Sub() InternalCollectFiles(d, pattern, queue))).ToArray())

    Catch e As UnauthorizedAccessException
    Catch e As SecurityException
    Catch e As DirectoryNotFoundException

    Catch ex As Exception
        MsgBox(String.Format("Error in 'InternalCollectFiles': {0}", ex.InnerException))

    End Try

End Sub