Ben kullanıcı adı için kullanıcı zorlukları bir PHP oturum açma komut dosyası kullanarak & am şifre.

Once authenticated program stores a session value. On logout, session value is set to blanks.

Here is the problem:

In IE 8 (not Firefox), user can hit back button a few times until the screen which shows "Web Page has expired" message. This is likely the login screen.

If he presses F5, it looks like username and password are still hanging around in POST variables and he gets logged back in.