hyperref: footnote link sbagliati

Preambolo:

`\documentclass[a4paper,12pt,openright]{book}
\usepackage[italian]{babel}
\usepackage[utf8]{inputenc}
\usepackage{natbib}
\usepackage[]{hyperref}
\usepackage[a4paper,top=5cm,bottom=6.2cm,right=4.4cm,left=4.4cm,bindingoffset=0mm]{geometry}
%\usepackage{classicthesis-ldpkg}
%\usepackage{classicthesis}
\usepackage{amsmath,amsfonts,amssymb}
\usepackage[onehalfspacing]{setspace}
\usepackage[font=small]{caption}
\usepackage[T1]{fontenc}
\usepackage{type1ec}
\usepackage{microtype} `

quando clicco su una numero di nota vengo riportato all’indice del documento.
In fase di comilazione compare il warning:

`name {Hfootnote 5} has been referenced but does not exist.replaced by a fixed one.`