主题：生成的excel报表，点预览在xp下能正常显示，在win7下在任何栏里，要再次点一下 才能正常显示在屏幕中 ，能否跟xp一样一点预览直接显示在屏幕中？

我的代码是这样的If  Tables("销售单").current("单据状态")="已审核"
    Dim Book As New XLS.Book(ProjectPath & "Attachments\销售单.xls")
    Dim fl As String = ProjectPath & "Reports\销售单.xls"
    Book.Build()
    Book.Save(fl)
    Dim App As New MSExcel.Application
    App.Visible = False
    App.Caption = "汉思软件"
    Dim Wb As MSExcel.WorkBook = App.WorkBooks.Open(fl)
    Dim Ws As MSExcel.WorkSheet = Wb.WorkSheets(1)
    App.Visible = True
    Ws.PrintPreview
    App.Quit
Else
   
    messagebox.show("已审核的单据才能打印!","信息提示",MessageBoxButtons.ok, MessageBoxIcon.warning)
    Return
End If
ShowAppWindow("销售单.xls",2)