In our office we have machines running both xl2000 and xl2003. The machine I
work on is 2000 and I have programmed some macros to make sheets very hidden.
Other macros reference these sheets and do calculations without having to
unhide them.

However, when running the application on xl2003, the sheets are hidden
properly, but when the calculating macros try to reference them error 9
occurs (out of range).

Any ideas as to why?

code (the following is just one of the places in the code that gets hung up.
I've got a lot of macros that are stopping because of this)
-----------------------------------------------------------
Private Sub ButtonGetMiles_Click()
Application.ScreenUpdating = False
Dim ChartRange As Object
Dim Loc1 As Object
Dim Loc2 As Object
Dim DistanceMiles As Variant
Dim DistanceKm As Variant
Dim TravelTime As Variant

***the code stops with the following line \/ \/ \/ *****
With Workbooks("Login (1.0)").Sheets("Mileage Info")
Set ChartRange = .Range("B2:FT176")
Set Loc1 = .Range("A201")
Set Loc2 = .Range("A204")
End With

DistanceMiles = Application.WorksheetFunction.Index(ChartRange, Loc1,
Loc2)
DistanceKm = DistanceMiles * 5 / 3
TravelTime = DistanceMiles / 60

If ComboLoc1.Value = "" Then
MsgBox "Please select a starting location."
ComboLoc1.SetFocus
Exit Sub
End If

If ComboLoc2.Value = "" Then
MsgBox "Please select a destination."
ComboLoc2.SetFocus
Exit Sub
End If

If ComboLoc1.Value = ComboLoc2.Value Then
MsgBox "Please choose two different destinations."
ComboLoc1.SetFocus
Exit Sub
End If

BoxMiles.Value = DistanceMiles
BoxKm.Value = DistanceKm
BoxTravelTime.Value = TravelTime
Application.ScreenUpdating = True
End Sub