File not found exception

public void ProcessRequest(HttpContext context)
{
    try
    {
        if (context.Session != null)
        {
            if (context.Session["CurrentUser"] != null)
            {
                string urlRequested = HttpUtility.UrlDecode(context.Request.Url.AbsolutePath);
                string filePath = HttpContext.Current.Server.MapPath(urlRequested);

                FileInfo thisFileInfo = new FileInfo(filePath);
                string fileExtention = thisFileInfo.Extension;

                context.Response.AddHeader("Content-Length", thisFileInfo.Length.ToString());

                //set content type
                DocumentTypeService documentTypesService = new DocumentTypeService();
                DocumentType currentType = documentTypesService.ReadByExtension(fileExtention.Replace(".", "").ToLower());

                if (fileExtention != null)
                {
                    context.Response.ContentType = currentType.ContentType;
                }
                context.Response.TransmitFile(filePath);
                context.ApplicationInstance.CompleteRequest();
                //context.Response.End();
            }
            else
            {
                context.Response.Redirect("~/Login.aspx");
            }
        }
        else
        {
            context.Response.Redirect("~/Login.aspx");
        }
    }
    catch
    {
        context.Response.Redirect("~/Login.aspx");
    }
}

context.Response.AddHeader("Content-Length", thisFileInfo.Length.ToString());