cant read memory crash when printing

I am writing VBA on a works computer, so I dont have admin rights etc on the
machine, so any solutions need to take that into account. The workbook is
under 1mb even when populated and the code runs in single step mode and 9
times out of 10 when run normally, but from time to time excel crashes with
a cant ready memory error at the point of me printing.

I have re-coded a whole section of the printing routine to stop the
execution of events loading info prior to print and that solved alot of the
crashes and it now works 9 times out of 10. I have also ensured every
userform is unloaded after use and there are no duplicate unloads.

The print code is very simple for the section excel falls over in. It tests
to see if the user has selected an entry from a list box, hides the listbox,
loads page with info, selects the page, prints, tests to see if the user
wants a letter, selects letter page, prints letter the no. of times set on
user form.

I am using excel 2000.

code:-

Private Sub cbSelected_Click()

Dim lItem As Long

ufAnimal_List.Hide

For lItem = 0 To Me.lbAnimal_Selection.ListCount - 1

If Me.lbAnimal_Selection.Selected(lItem) = True Then

Worksheets("animal Card").Range("B16").Value =
Worksheets("workpage").Range("BV" & _
(7 + lItem)).Value
Worksheets("animal Card").Range("B23").Value =
Worksheets("workpage").Range("BW" & _
(7 + lItem)).Value
Worksheets("animal Card").Range("B23").Value =
Worksheets("animal Card").Range("B23").Value + _
". " + Worksheets("workpage").Range("CF" & Search_Line("CE",
_
Worksheets("workpage").Range("CG5").Value, _
Worksheets("workpage").Range("BS" & (7 +
lItem)).Value)).Value

Worksheets("Animal Card").Select

'ActiveSheet.PrintPreview
ActiveWindow.SelectedSheets.PrintOut Copies:=1

'If print letter option selected then print letter
If (Worksheets("workpage").Range("G61").Value = True) Then

Worksheets("Animal Letter").Select
'Print no. copies of letter one for customer and other for
walk log
ActiveWindow.SelectedSheets.PrintOut
Copies:=Val(Me.tbCopies.Text)

End If

Me.lbAnimal_Selection.Selected(lItem) = False

End If

Next lItem

End Sub

Any ideas on why it would be crashing when printing?

Anthony