PDFs when you save them. The PDF is saved on your computer, so it opens automatically when I download the file. Is this possible to me to stop them from opening? Voted Best Answer · Firefox Add-ons. Open the Reader Settings. Select General > Accessibility. Click on the button labeled Stop the Adobe Reader From Opening After I Save PDFs to view all the options. Once opened click “Advanced”. Next to PDF Viewer : Select Automatic. Click “Done” Close the Reader. Close all of your bookmarks that use Adobe reader, so they don't reopen. You can close Chrome with Ctrl + T or by typing in Ctrl + Shift + Delete : Close Chrome. Click on the “Close Add-ons and extensions” button. On the bottom of the page click Save Changes. Do I have to have Auto Save on in order to stop PDFs from opening automatically? Yes, You need to have the feature enabled in order to stop it. In any other form, it won't work.