Webpage has expired

Hi, I'm facing trouble here when user click back button in the browser after login it give him (Webpage has expired). Can someone help here regard this matter. Thanks. My code Page2. <html> <body> <form action="test3.php" method="post"> Username: <br><input type="text" name="username"></br> <input type="submit" name = 'submit1' value= 'Login'> </form> </body> </html> Page3. <?php session_start(); ?> <html> <body> <?php $username = $_POST['username']; $_SESSION['username']= $_POST['username']; echo "<br> Hi $username.</br>"; ?> <form action="test4.php" method="post"> <input type="submit" name = 'submit' value= 'click me'> </form> </body> </html> Page4. <?php session_start(); $username = $_SESSION['username']; echo "<br> Hi $username.</br>"; ?> Php.ini Session Support enabled Registered save handlers files user sqlite Registered serializer handlers php php_binary session.auto_start Off Off session.bug_compat_42 Off Off session.bug_compat_warn Off Off session.cache_expire 180 180 session.cache_limiter nocache nocache session.cookie_domain no value no value session.cookie_httponly Off Off session.cookie_lifetime 0 0 session.cookie_path /tmp /tmp session.cookie_secure Off Off session.entropy_file no value no value session.entropy_length 0 0 session.gc_divisor 1000 1000 session.gc_maxlifetime 1440 1440 session.gc_probability 1 1 session.hash_bits_per_character 5 5 session.hash_function 0 0 session.name PHPSESSID PHPSESSID session.referer_check no value no value session.save_handler files files session.save_path /tmp /tmp session.serialize_handler php php session.use_cookies On On session.use_only_cookies On On session.use_trans_sid 0 0 Regards -Hadi

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