ti inserisco il tutto 
riservato:
codice:
<%
Response.CacheControl = "no-cache"
Response.AddHeader "pragma", "no-cache"
Response.Expires = 0
%>
<%
if Session("Autenticato")<>"OK" then
Response.Redirect("index_new.asp")
end if
%>
<HTML>
<HEAD>
<TITLE>Area riservata</TITLE>
</HEAD>
<BODY BGCOLOR=#BBBBFF>
<DIV ALIGN=CENTER><H1>PAGINA RISERVATA</H1>
<H2>UTENTE AUTENTICATO</H2>
</DIV>
</BODY>
</HTML>
index_new:
codice:
<html>
<head>
<title>Accesso all'area riservata</title>
</head>
<body bgcolor="#0099FF" text="#000000">
<div align="center">
</p>
<HTML>
<HEAD>
<TITLE>Autenticazione utente tramite password</TITLE>
<BODY BGCOLOR=#BBBBFF>
<FORM ACTION="login.asp" METHOD="POST">
<input type="hidden" name="from" value="undefined">
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">USERNAME:</font>
<INPUT TYPE=TEXT NAME="nome_utente" size="25" maxlength="20">
</p>
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">PASSWORD:</font>
<INPUT TYPE=PASSWORD NAME="password" size="25" maxlength="20">
</p>
<INPUT TYPE=SUBMIT NAME="show" VALUE="LOGIN">
</p>
</FORM>
</div>
</body>
</html>
Grazie