title: how to stop google crawl unexisting page
body: <p>When I was developing my site. I made a typo in one place, for example, all my pages are dir1/dir2/page.htm/par1-par2, but my typo was dir1/dir2/page/par1-par2 (note: without .htm).</p>
  
  <p>It was in production for 1 day only, but Google is keep crawling those links. How to stop Google doing that?</p>
  
  <p>By the way, that's not 1 page, but hundreds or thousands of pages.</p>