Check your PDF Plugins are updated!

• http://www.mozilla.org/en-US/plugincheck/

Goto > Mozilla Menu > Tools > Options

• Application > Search for "PDF" and change the action to "VIew in built-in PDF" or choose adobe reader.

For more

• https://support.mozilla.org/en-US/kb/view-pdf-files-firefox-without-downloading-them

No sorry it didn't help. All plug-ins are up to date but it still doesn't work

Hello,

The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information.
Note: This will cause you to lose any Extensions and some Preferences.

• Open websites will not be saved in Firefox versions lower than 25.

To Reset Firefox do the following:

1. Go to Firefox > Help > Troubleshooting Information.
2. Click the "Reset Firefox" button.
3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
4. Firefox will open with all factory defaults applied.

Further information can be found in the Refresh Firefox - reset add-ons and settings article.

Did this fix your problems? Please report back to us!

Thank you.

Check your settings under Firefox Options > Applications. Make sure the PDF settings.

Hi guys thanks for trying to help but absolutely nothing works. I simply don't know what else to try except giving up and using IE instead but I love using Firefox. Are there others out there in the same boat as me?

Current Firefox versions have enabled a built-in PDF Viewer that doesn't have all features that other PDF readers like the Adobe Reader have or may not function properly otherwise.

You can change the action for Portable Document Format (PDF) from Preview in Firefox to use another application like the Adobe Reader or set to Always Ask in "Firefox > Options/Preferences > Applications".

You can set the pdfjs.disabled pref to true on the about:config page to disable the build-in PDF viewer.

You can check the value of the plugin.disable_full_page_plugin_for_types pref on the about:config page and remove the application/pdf part if present or reset the pref to the default via the right-click context menu if you want to display PDF documents in Firefox with another application (i.e. not the built-in PDF Viewer).

• http://kb.mozillazine.org/about:config

See also:

• https://support.mozilla.org/kb/view-pdf-files-firefox-without-downloading-them

Ok tried that again but still no joy. Hours on this today and I have to give up tonight. I think Firefox just doesn't display PDF any more. I hope you will come up with a solution. Thank you

Did you check the location bar to see if there is a shield icon or a Lego icon that would indicate that content is blocked?

• https://support.mozilla.org/kb/why-do-i-have-click-activate-plugins
• http://kb.mozillazine.org/Issues_related_to_plugins#Click_to_Play

Hello,

Certain Firefox problems can be solved by performing a Clean reinstall. This means you remove Firefox program files and then reinstall Firefox. Please follow these steps:

Note: You might want to print these steps or view them in another browser.

1. Download the latest Desktop version of Firefox from http://www.mozilla.org and save the setup file to your computer.
2. After the download finishes, close all Firefox windows (click Exit from the Firefox or File menu).
3. Delete the Firefox installation folder, which is located in one of these locations, by default:
   • Windows:
     • C:\Program Files\Mozilla Firefox
     • C:\Program Files (x86)\Mozilla Firefox
   • Mac: Delete Firefox from the Applications folder.
   • Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
4. Now, go ahead and reinstall Firefox:
   1. Double-click the downloaded installation file and go through the steps of the installation wizard.
   2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

Please report back to see if this helped you!

Thank you.

I have already tried re-installing Firefox but that didn't work. However I have found this morning that its not just PDF files that won't open, its Word documents and Excel spreadsheets too. I am not in front of my PC now as I am at work so can't check the shield icon. However when I open files in IE a box comes up at the bottom of the screen asking to show content. Then I can open the file. I'll get back on the case later when I get home. Thanks Ray Walker

Have you tried to re-install your viewer? BTW, what viewer are you using?

using adobe reader and I have already re-installed it

no I don't see a sheild anywhere

Is this problem specific to a particular site? For example, email attachments don't open, but if you find a PDF or DOC file in a Google search, that one will open?

Example of PDF documents on Microsoft site related to security: https://www.google.com/search?q=site%3Amicrosoft.com+security+filetype%3Apdf

yes you are right its only in e-mail attachments where I have the problem

Something in this thread about Yahoo attachments might be relevant: Firefox suddently stopped downloading email attachments. Does anything there help?

Well, I klick the attachment, then for a moment it says "Scanning attachment" in the mail preview pane and after that, when the download should normally start, nothing happens.

This was from someone with the same problem

Hi lizipilot, two other things from that thread.

(1) Did you test whether you have the same issue in Firefox's Safe Mode? That's a standard diagnostic tool to bypass interference by extensions (and some custom settings). More info: Diagnose Firefox issues using Troubleshoot Mode.

You can restart Firefox in Safe Mode using

Help > Restart with Add-ons Disabled

In the dialog, click "Start in Safe Mode" (not Reset)

Any difference?

(2) Did you want to try temporarily disabling Firefox's integration with Windows' own attachment security feature? This thread has the steps for changing that setting: Downloaded files instantly disappear on completion.

tried safe mode no different unfortunately

I have the same problem too. Somehow the latest Firefox update messed up the ability to preview Adobe file within it's browser.

I tried everything above as well. No luck.

I do have a solution now. That is to uninstall Firefox and use IE or Chrome.

Farewell Firefox!