Prevent Adobe Reader From Opening PDFs in the Browser

By default, Adobe Reader and Adobe Acrobat integrate into Internet Explorer and cause PDF files to be opened automatically by the browser.

This confirmation-less rendering of PDF files have enabled attackers to automatically deliver Adobe Reader and Acrobat exploits via the internet. The end result: surreptitious malware downloads to your computer.

Fortunately, there is an easy way to prevent Adobe Reader and Acrobat from automatically rendering PDF files in your browser. Make this one small tweak, and henceforth you'll be notified if a website tries to open a PDF in your browser.

1. Open Adobe Reader or Adobe Acrobat.
2. Open the Edit > Preferences... menu from the menu bar. Ctrl+K is the shortcut key to get there even quicker.
3. From the left pane, select Internet.
4. Uncheck the box next to Display PDF in browser.
5. Choose the OK button to save and exit the settings window.