Fatal Error When I Regen

I have had a problem (VBA 2000 & 2004) with ThisDrawing.Regen
acActiveViewport. Occasionally I get a fatal error(FATAL Error: Unhandled
Access Violation Reading 0x0000 Exception at ????? ). I pass a string of
layers (format: "Layer1,Layer2,Layer3") into the sub below and when there is
a crash, the crash point is always the line: ThisDrawing.Regen
acActiveViewport. Before and after this sub, I am changing layouts and
plotting. I have noticed when in 2004 that if I set the LAYOUTREGENCTL to
0, all seems to work fine. I would like to get this to work for both 2000
(2000 does not have LAYOUTREGENCTL variable) & 2004. Does anyone have any
insight on what is causing the problem?

Thanks.

Chris


Private Sub TurnOnLayers(strPassedLayers As String)
Dim objLayer As AcadLayer
Dim strLayer As String

ThisDrawing.ActiveLayout = ThisDrawing.Layouts("Model")
If ThisDrawing.Layers("0").Freeze = True Then
ThisDrawing.Layers("0").Freeze = False
End If

ThisDrawing.ActiveLayer = ThisDrawing.Layers("0")
ThisDrawing.Application.Update

On Error Resume Next
For Each objLayer In ThisDrawing.Layers
objLayer.Freeze = True
Next objLayer

strLayer = ""

Dim i As Long
For i = 1 To Len(strPassedLayers)
If Mid$(strPassedLayers, i, 1) = "," Or i = Len(strPassedLayers) Then
If i = Len(strPassedLayers) Then
strLayer = strLayer & Mid$(strPassedLayers, i, 1)
End If
On Error Resume Next
ThisDrawing.Layers(strLayer).Freeze = False
On Error Resume Next
ThisDrawing.Layers(strLayer).LayerOn = True
strLayer = ""
Else
strLayer = strLayer & Mid$(strPassedLayers, i, 1)
End If

Next i

ThisDrawing.Regen acActiveViewport

End Sub