When you clicked PDF file, modern browser such as Chrome display the content instead of downloding the file. If you want the browser to always download the PDF files, you need to tweak your web server. Using apache server, you can use the following tricks in your apache conf :

You need to make sure you enable mod_headers module.

<FilesMatch "\.(?i:pdf)$">
  ForceType application/octet-stream
  Header set Content-Disposition attachment
</FilesMatch>

or the more simple one is :

AddType application/octet-stream .pdf

May 12th, 2011 | Del.icio.us | Digg | Stumble | Comments(2)