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NSPR4.DLL Missing Error Message. How do I fix this?

MarshallTSL
MarshallTSL
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About 60 days ago, I started getting an error message when I would start Firefox (but only Firefox). If I clicked "OK" on the error message dialog box, Firefox would load. I did notice that it's become very flaky and would constantly crash, especially if Facebook was one of the open tabs.

Also, about 60 days ago, links in Outlook 2013 email would not launch in Firefox. I could copy and past, but I couldn't launch directly from Outlook.

Any ideas?

About 60 days ago, I started getting an error message when I would start Firefox (but only Firefox). If I clicked "OK" on the error message dialog box, Firefox would load. I did notice that it's become very flaky and would constantly crash, especially if Facebook was one of the open tabs. Also, about 60 days ago, links in Outlook 2013 email would not launch in Firefox. I could copy and past, but I couldn't launch directly from Outlook. Any ideas?

All Replies (1)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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Is that file still part of Firefox? Hmm... please try the following in this order, I'll give you all the details:

(1) Clean Reinstall (details below) (2) Start in Safe Mode (details below) (3) Minimize Plugins (details below)

Clean Reinstall

We use this name, but it's not about removing your settings, it's about making sure the program files are clean (no inconsistent or alien code files). As described below, this process does not disturb your existing settings. Do NOT uninstall Firefox, that's not needed.

(1) Download a fresh installer for Firefox 38.0.5 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.)

(2) Exit out of Firefox (if applicable).

(3) Rename the program folder:

(64-bit Windows folder names) 

C:\Program Files (x86)\Mozilla Firefox

to 

C:\Program Files (x86)\OldFirefox

(32-bit Windows folder names) 

C:\Program Files\Mozilla Firefox

to 

C:\Program Files\OldFirefox

(4) Run the installer you downloaded in #1. It should automatically connect to your existing settings.

Will a cleanly reinstalled Firefox load Google correctly?

Note: Some plugins may exist only in that OldFirefox folder. If something essential is missing, look in these folders:

  • \OldFirefox\Plugins
  • \OldFirefox\browser\plugins

To start up in Firefox's Safe Mode:

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

  • "3-bar" menu button > "?" button > Restart with Add-ons Disabled
  • Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

To minimize plugins:

Open the Add-ons page using either:

  • Ctrl+Shift+a
  • "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Plugins. On the right side, set all plugins you can live without for 24 hours to "Never Activate". I suspect that would be everything except Shockwave Flash.

Any improvement?