php session post problem

/////////////temp1.php//////////////

<?php
session_start();
echo "<title>akshay</title>";
$username=$_POST['username'];

echo "$username";

echo "<form name=one action=temp1.php method=post>";
echo "Username <input type=text name=username><br>";
echo "<input type=submit>";
echo "<a href=http://www.financialanalyststudy.com/a.php>Navigate</a>";

?>

////////////////a.php/////////////////
<?php
session_start();
echo session_id();

?>


the error occurs in Internet explorer and not in firefox

the above is the script of two file temp1.php and a.php

submit the data in temp1.php
it shows the username
then i click the navigate hyper link to go to a.php
then i click the back button on the browser tool bar to return to temp1.php
and i get "The page cannot be displayed" when i refresh i get the username again with the seesion.

 

The The page cannot be displayed error could be caused as you are trying to re-post the data to get the username.

 

i would like you to elaborate on it with a small example

 

He means, when you go back, you get "The page cannot be displayed error " because you have used $_POST[''] submit before.
If you used $_GET[''], then you will see the page just fine.

 

i want to do it using post itself $_POST['']

 

There is no real other way unless you do it with GET or SESSIONS.

Other then that, good luck.