When you click a PDF link on a webpage, it can either open in the web browser or directly in Acrobat or Reader.
Each browser has its own setting to control how PDFs open from a web page. To change the display behavior, follow the instructions below for your browser or see the browser documents on how to control plug-ins or add ons.
1. Open Internet Explorer
2. Choose Tools > Manage Add-onsChoose Tools > Manage Add-ons
3. Select Toolbars and ExtensionsSelect Toolbars and Extensions
4. In the Show menu, select All Add-onIn the Show menu, select All Add-on

5. In the list of add-ons, select Adobe PDF Reader.
Top Tip: If you don’t see the Adobe PDF Reader add-on, try the other options on the menu. For example, on some systems, the add-on appears when you select Run Without Permission.
6. Click Enable or Disable (it changes depending on the status of the selected add-on):
• Enable sets the Adobe PDF Reader add-on to open PDFs in the browser.
• Disable turns off the add-on so it doesn’t open PDFs in the browser.

For more information, see the Internet Explorer help topic Using the Internet Explorer 8 Add-on Manager or How to manage add-ons in Internet Explorer 9
1. Open Chrome, and type in chrome://plugins
2. Find the Adobe PDF plug-in, and do one of the following:
- To have the Adobe PDF plug-in open PDFs in the browser, click Enable.
- To use the Chrome PDF Viewer instead, click Disable. The Chrome PDF Viewer becomes enabled.
- To have Chrome download PDFs instead, shift-click Disable for the currently enabled viewer. This leaves both viewer plug-ins disabled so the PDFs won't display in the browser.

For more information, see the Google Chrome help topic Plug-ins.
- Choose Tools > Add-ons.
- In the Add-ons Manager, click Plugins.
- Select Acrobat or Reader plugin.
- Click Enable or Disable (it changes depending on the status of the selected add-on):
- Enable sets plugin to open PDFs in the browser.
- Disable turns off the plugin so it does not open PDFs in the browser
For more information, see the Mozilla Firefox help topic Using a PDF Reader Plug-in.
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 Change All.

5. Select Change All in the Open With panel.
6. When asked if you want to change all similar documents, click Continue.
Top Tip: You must have root user privileges to change the Safari plug-ins.
To display PDFs using the Safari PDF viewer, you must disable the Adobe PDF Viewer.
1. Quit Safari.
2. Log in as the root user.
Top Tip: The root user privileges aren't enabled by default because the root user can change system files. For more information and instructions, see one of the following Apple documents Enabling and using the "root" user in Mac OS X or OS X Mountain Lion: Enable and disable the root user.
3. Choose Go > Go To Folder.

4. Type /Library in the Go To The Folder field, and click Go.

5. Create a new folder in the Library folder, and name it Internet Plug-ins Disabled.

6. Open the Internet Plug-ins folder, and move both the AdobePDFViewer.plugin and the AdobePDFViewerNPAPI.plugin into the new Internet Plug-ins Disabled folder.

Top Tip: If both Adobe PDF Viewer plug-ins are still in the Internet Plug-ins folder, drag them now to the trash. You may be asked for your name and password.
For more information, see the Apple Safari help topic If you need to remove a plug-in.