Under Add-on Types, select Toolbars And Extensions.

Open Internet Explorer, and choose Tools > Manage Add-ons.

* To disable in browser PDF viewing, select save file. Enable the Acrobat or Reader plugin by select “Always Active” Next open option windows, under Applications tab Select Use Adobe Acrobat (in Firefox) for Adobe Acrobat Forms Document, Adobe Acrobat XML Data Package File, and Portable Document Format (PDF). Mozilla Firefox Press Ctrl+Shift+A to open the Add-ons Manager window.

To disable in browser PDF viewing and force Chrome download PDF files, leaves both viewer plug-ins disabled so the PDFs won’t display in the browser.

To make Adobe PDF plug-in the default PDF viewer in the browser, enable the Adobe PDF plug-in and disable Chrome PDF Viewer.

Locate the Adobe PDF plug-in, and do one of the following:

Google Chrome Open Chrome, Type chrome://plugins in the address bar to open the Plug-ins page.

To change the default PDF view in web browsers, follow the instructions to active the Adobe PDF reader plug-ins or add-ons. This viewer might not display all PDF documents correctly. Some PDF files have special arrangements or contain extra functions would have issues when viewing it with built-in PDF viewer. However, the built-in viewers are not compatible with all PDF files. It allow users to view PDF without installing Adobe PDF reader. The built-in PDF viewer is enabled by default. Firefox, Chrome, and the latest version Internet Explorer now have a built in PDF reader.

Adobe pdf viewer for firefox