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i updated my firefox from 17 to 19. now nothing in my add-ons extensions work and my plugin doesn't work


in the middle of updating, my computer crashed. i restarted firefox and it was 19 instead of 18. then when i checked my add-ons. everything was disabled and most were gone!... then i went to plug-ins for an update and it doesn't even run anymore. somehow it did save my old firefox in a folder on my desktop but i don't know how to work it.

i've always updated my firefox and never had a problem. but now nothing works and i need everything to be restored.

Additional System Details

Installed Plug-ins

  • Next Generation Java Plug-in 10.11.2 for Mozilla browsers
  • Shockwave Flash 11.5 r502
  • Adobe PDF Plug-In For Firefox and Netscape 10.1.5
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
  • iTunes Detector Plug-in
  • Google Update
  • VLC media player Web Plugin 2.0.2
  • 5.1.10516.0
  • Unity Player 3.4.2f3
  • npapicomadapter
  • The Hulu Desktop Plugin allows Hulu.com to integrate with the Hulu Desktop application.
  • The plug-in allows you to open and edit files using Microsoft Office applications
  • Office Authorization plug-in for NPAPI browsers


  • User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:19.0) Gecko/20100101 Firefox/19.0

More Information

  • Top 10 Contributor
  • Moderator
2042 solutions 8887 answers

hello, your question conatins a few issues...

  • if you want to use the regular release version (firefox 18.0.2 at the moment) and not a beta version, then please download the setup file from getfirefox.com & install it on top of your current installation
  • when there is a folder named "old firefox data" on your desktop, then you've done a reset of firefox which had reset most of your preferences to the factory default & removed all extensions. if you want to revert that, go to firefox > help > troubleshooting information and click on profile folder/show folder. a windows explorer window should open up. now close all open firefox windows and replace all the contents of your current profile folder with the data that is stored inside the "old firefox data" folder on your desktop.
  • the plugin check website isn't working at the moment - so the problem you're seeing here isn't on your end. hopefully this will be fixed soon on the server-side...
  • Top 25 Contributor
  • Moderator
437 solutions 3143 answers

The reason you went from 17.0.* to 19.0 is likely because you were on the Beta channel due to using a Beta build at some point. A easy way to get back on the Release channel is to download and install 18.0.2.

Question owner

thank you very much. another question is that my idm and norton toolbar both won't work on my add-ons. if i do restore it from my old firefox folder and those still don't work then what should i do?

  • Top 10 Contributor
  • Moderator
2042 solutions 8887 answers

run symantec live update in order to obtain the latest version of the toolbar that is compatible with firefox 18: https://community.norton.com/t5/Norton-Toolbar-Norton-Identity/Firefox-18-Support-for-Norton-Toolbar/td-p/886714

i don't know about the compatibility of idm, but you could use a different addon like DownThemAll! which will work well in current versions of firefox.

  • Top 25 Contributor
  • Moderator
437 solutions 3143 answers

Norton only supports Trelease builds and not Test builds like Beta. Though if you did install Firefox 18.0.2 you probably have to do Norton live update until it works.

lilmamakim 0 solutions 1 answers

I somehow ended up with a different version of firefox also, and tried the help troubleshooting thing, and it isnt working. It tells you to TRANSFER the old file, but not exactly HOW to do it. Im completely disgusted and about to quit firefox!

  • Top 10 Contributor
  • Moderator
10737 solutions 96600 answers

It is possible that there is a problem with the file(s) that store the extensions registry.

Delete the extensions.* files (e.g. extensions.sqlite, extensions.ini) and compatibility.ini in the Firefox profile folder to reset the extensions registry.

New files will be created when required.

See "Corrupt extension files":

If you see disabled, not compatible, extensions in "Tools > Add-ons > Extensions" then click the Tools button at the left end side of the Search Bar ("Find Updates" button in older Firefox versions) to check if there is a compatibility update available.

If this hasn't helped then also delete the addons.sqlite file.