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{ 2005 09 14 }

The Mozilla Default Plug-in

By default, Mozilla Firefox comes with the file npnul32.dll in the \Plugins\ directory. If you enter about:plugins in the location bar, you’ll see a list of installed Plug-ins, with file information, and MIME-type assignments. In that list, you’ll see npnul32.dll listed as “Mozilla Default Plug-in”, assigned to the MIME-type *.
So what is the Mozilla Default Plug-in? What does it do? Why is it there? Can one disable it? How does one disable it?

The Mozilla default plug-in is the plugin finder that gets initiated, when you try to load a page that requires a plug-in, which is not found. Whether or not the default plug-in is enabled or disabled dictates how the plugin finder works.
For instance, if don’t have the Macromedia Flash plug-in, then go to their test page, this is what you’ll get with the default plug-in disabled:
[screenshot]

This is what you’d get, if the default plug-in is enabled (click on it for full size):
[screenshot]

To enable the Mozilla Default plugin, use about:config to change the pref plugin.default_plugin_disabled to false

Posted by Chris Ilias on Wednesday, September 14, 2005, at 11:30 pm. Filed under Firefox, Mozilla. Follow any responses to this post with its comments RSS feed. Both comments and trackbacks are currently closed.

{ 15 } Comments

  1. Luccks | February 1, 2006 at 3:18 pm | Permalink

    Tank’s for your post. I resolve my problem, exactly same. []’s

  2. Karie | February 22, 2007 at 12:18 am | Permalink

    I recently updated to Firefox 2.Now, websites are not loading correctly. I can no longer see all images and backgrounds,or colors on web sites.
    I have tried changing settings, updated all plugins-I have tried everything that the Firefox help forums have suggested.I also tried enabling the mozilla default plugin as you described above.Any other ideas? This is driving me crazy!
    Thanks.

  3. jennifer | March 10, 2007 at 12:50 am | Permalink

    Karie…I have the exact same problem as you after installing Firefox 2…did you find any solution.

    THANKS

  4. Jason | March 27, 2007 at 11:05 am | Permalink

    Thanks for the troubleshooting tips! That’s been bugging me for months.

  5. Diane | April 21, 2008 at 2:10 pm | Permalink

    I believe this is why I could not download my class videos. Thanks.

  6. viktor | May 18, 2008 at 1:59 pm | Permalink

    thanks man!! that solved my problems, i love you:P

  7. viktor | May 18, 2008 at 2:05 pm | Permalink

    What!!! i cant it does no difference if i enable plugin.default_plugin_disabled to false :S it worked before

  8. Drmarx | May 22, 2008 at 11:45 pm | Permalink

    I want to know firefox can automatically download the missing plug ins like IE does.

  9. mdda | July 20, 2008 at 1:38 am | Permalink

    Haha! Downloading plugins automatically is the massive security hole that is the downfall of IE. DO NOT WANT.

  10. ulligaka | September 12, 2008 at 11:28 am | Permalink

    Brilliant it worked like a charm for me (firefox 2.0.0.16). Remember to restart firefox to make it work.

  11. Ben | September 24, 2008 at 9:41 am | Permalink

    it didnt work

  12. Don | December 19, 2008 at 11:33 am | Permalink

    Is this plug in installed and enabled in update firefox 3.05 ?

  13. Bashiieru | August 30, 2009 at 7:33 pm | Permalink

    Duudee thank you soooooo much, aru! 8D

  14. Alan Baxter | October 24, 2009 at 10:26 am | Permalink

    You appear to have been hacked. View Source shows there is a hidden iframe with a link to a malicious site at the end of the page. I’ve broken the link here.

  15. Alan Baxter | October 24, 2009 at 11:03 am | Permalink

    “I’ve broken the link here.”
    Apparently the link was stripped from my comment. Just look for the hidden iframe.

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