Disabling explorer's back button

Hi;

I want to prevent users pressing the browser's back button but how?? disable it

Thanks for your replies from now........

1. open page in new window without tools and menu

2.disabled rightbutton

I'll try to explain you my problem.The problem rounds around 3 page.
1-login.asp
2.documentationpage.htm
3.show.asp

login.asp-->documentation.htm and when click on a link on this page -->show.asp(shows some documents)

now when coming back from show.asp,it directly goes to login.asp,I want it to go to documentationpage.htm.The code on documentation.htm is as follows:

function unload() {

window.location.replace='http://vkomdeneme/Vestelweb/logout.asp';
}

the aim of this function is,when the user just closes the browser without logging out,it runs the logout.asp program.This logout.asp program:

<!--#include file="Tools.asp"-->
<%
OpenAddress con
SQL="UPDATE tblLog SET fldTimeOut= '" & Time() & "' WHERE fldUserName= '" & session("admin" ) & "'"
con.execute(SQL)
SQL="UPDATE tblLog SET fldOffline=1 WHERE fldUserName='" & session("admin" ) & "'"
con.execute(SQL)
con.close
response.redirect("login.asp" )
%>

window.location.replace //goes documentationpage.htm when pressing back button of explorer on show.asp page but logout.asp program doesn't execute

window.location.href //logout.asp execute but,directly jumps to the login.asp

please help me !!!

try this:

thank you