IE7 opening excel files.

may not be working , check out : http://blogs.msdn.com/excel/archive/2006/09/26/771221.aspx

   Public Shared Sub ExportToExcel(ByVal objViewcreator As ViewCreatorGeneral, ByVal dtFromDatabase As DataTable, ByVal inColumnArrList As ArrayList, ByVal report_header As String, ByVal originalSort As String)

        System.Web.HttpContext.Current.Response.ClearContent()
        System.Web.HttpContext.Current.Response.ClearHeaders()
        System.Web.HttpContext.Current.Response.Charset = ""
        System.Web.HttpContext.Current.Response.ContentType = "application/vnd.ms-excel"
        System.Web.HttpContext.Current.Response.AddHeader("Content-Disposition", "inline; filename=report.xls")
        System.Web.HttpContext.Current.Response.AddHeader("Pragma", " private")
        System.Web.HttpContext.Current.Response.AddHeader("Cache-control", " private, must-revalidate")

        'writing tab separated stuff here
        Dim tabFile As String = "my tab separted cols crlf separeted rows"
        System.Web.HttpContext.Current.Response.BinaryWrite(Encoding.GetBytes(tabFile))

         System.Web.HttpContext.Current.Response.End()
    End Sub

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