I have the following code in a workbook. It works fine when the worksheets
inside the workbook are protected but not when the workbook is shared. Is
there any way to make this work on the shared workbook?

Option Explicit
Private Sub Workbook_SheetChange(ByVal Sh As Object, ByVal Target As Range)

Dim iRange As Range
Dim Cross1 As Range
Dim Cross2 As Range

Set Cross1 = Intersect(Target, Range(Cells(2, 6), Cells(30, 6)))
Set Cross2 = Intersect(Target, Range(Cells(2, 6), Cells(30, 6)))

If Not Cross1 Is Nothing Or Not Cross2 Is Nothing Then
For Each Target In Sh.Range(Cells(2, 6), Cells(30, 6))
If ((Cross1.Value = "D") And (Cross2.Value2 < "C")) Then
Sh.Tab.ColorIndex = 3
ElseIf Cross2.Value2 = "C" Then
Sh.Tab.ColorIndex = 5
Else
Sh.Tab.ColorIndex = xlColorIndexNone

End If
Next
End If