This FAQ contains instructions for changing the PDF viewer on the following browsers :

Chrome

1. In the Chrome address bar, type chrome://plugins
2. Disable Chrome PDF Viewer.
3. Enable the Adobe Acrobat/ Adobe Reader plugin

Firefox

1. At the top of the Firefox window, click on the Firefox button and then select Options
2. Select the Applications panel.
3. Find Portable Document Format (PDF) in the list and click on it to select it.
4. Click on the drop-down arrow in the Action column for the above entry and select the PDF viewer you wish to use.
5. Click OK to close the Options window

Internet Explorer

1. Open Internet Explorer, and choose Tools > Manage Add-ons.
2. Under Add-on Types, select Toolbars And Extensions.
3. In the Show menu, select All Add-ons.
4. In the list of add-ons, select Adobe PDF Reader.
5. Click the Enable or Disable button (it toggles depending on the status of the selected add-on)

Apple Safari

1. In the Finder, select a PDF, and choose File > Get Info.
2. Click the arrow next to Open With to expose the product menu.
3. Choose either Adobe Acrobat or Adobe Reader from the application menu.
4. Click the Change All button.
5. When asked if you want to change all similar documents, click Continue.