FitPagesDown problem

Hi! I'm using this code: Excel.Clear(); Excel.Sheets.Clear(); Excel.CompatibilityMode = CompatibilityMode.Excel2007; Excel.DefaultFont = new Font("Microsoft Sans Serif", 8F, FontStyle.Regular); XLSheet Sheet = Excel.Sheets.Add("sheet"); Sheet.PrintSettings.MarginTop = 0.5F; Sheet.PrintSettings.MarginBottom = 1F; Sheet.PrintSettings.MarginLeft = 0.5F; Sheet.PrintSettings.MarginRight = 0.5F; Sheet.PrintSettings.CenterHorizontal = true; Sheet.PrintSettings.CenterVertical = false; Sheet.PrintSettings.FitPagesAcross = 1; Sheet.PrintSettings.FitPagesDown = 100; Sheet.PrintSettings.AutoScale = true; But FitPagesAcross/FitPagesDown are always 1/1 in Excel after I open the saved xlsx file. Even when I set AutoScale to false... I'm doing something wrong ?

up, plz :$