title: PHP document expired on form post
body: <p>I have page 1 with form (POST) that posts to page 2 that if form POSTed shows result if form is not POSTed and page 2 open it shows other content based on PHP <code>if</code>.
  Page 2 has link to page 3 and when i post form from page 1 -> page 2 and go to page 3 via link then i click back and get "Document expired" </p>
  
  <p>Someone told me its n normal, however why's that happening? I assumed if PHP check's POST variable not exists and gives different content to page it should how fine. </p>
  
  <p>Is there any way's to make it work or its coded into browser to behave like that?</p>
  
  <p>Edit Answer: <code>&lt;?php session_cache_limiter('private_no_expire'); ... ?&gt;</code> fixed it</p>