Hello!

I am trying to write an xla-file that runs a macro when a xls-file is
opening (this is actually my first xla-file)
Then it should look in the xls sheet and if the cells(1,1) is "L" then it
should format the xls sheet page setup.

The problem is that the xls filename and sheetname isn't known. And I can't
make it to work to look in cells in the xls-file.
Here is the code in the xla-file (works if I add it to an xls-file):

Private Sub Workbook_Open()
If Cells(1, 1) = "Orientation L=Landscape" And Cells(2, 1) = "Fit A4 width
TRUE=Fit" Then
ActiveSheet.PageSetup.PrintArea = ""
With ActiveSheet.PageSetup
If Cells(1, 2) = "L" Then .Orientation = xlLandscape
.Zoom = False
If Cells(2, 2) = "TRUE" Then .FitToPagesWide = 1: .FitToPagesTall =
100
End With
End If
End Sub

The error message I get when I opens the xls-file is:
Run-time error '1004':
Method 'Cells' of object '_Global' failed

It seems like the workbook (xls) isn't available or in focus when the code
is running.
Could anyone help me to solve this?
Regards Magnus