Recent answers to Open pdf's in acroread (instructions at disable-built-pdf-viewer-and-use-another-viewer have no effect)https://support.mozilla.org/en-US/questions/9987912014-05-05T09:12:09-07:00Did you set the pdfjs.disabled pref to true on the about:config page?
That should be enough to disab2014-05-05T09:12:09-07:00cor-elhttps://support.mozilla.org/en-US/questions/998791#answer-569352<p>Did you set the pdfjs.disabled pref to true on the <b>about:config</b> page?
</p><p>That should be enough to disable the built-in PDF Viewer
</p><p>You can rename (or delete) the mimeTypes.rdf file in the Firefox profile folder to reset all file actions.
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<ul><li><a href="http://kb.mozillazine.org/mimeTypes.rdf" rel="nofollow">http://kb.mozillazine.org/mimeTypes.rdf</a>
</li><li><a href="http://kb.mozillazine.org/File_types_and_download_actions#Resetting_download_actions" rel="nofollow">http://kb.mozillazine.org/File_types_and_download_actions#Resetting_download_actions</a>
</li></ul>