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Spell checker not working


Since upgrading to Firefox 5, the spell checker no longer works.

Additional System Details

This happened

Every time Firefox opened

This started when...

upgraded to version 5

Installed Plug-ins

  • Shockwave Flash 10.3 r181
  • iTunes Detector Plug-in
  • Next Generation Java Plug-in 1.6.0_26 for Mozilla browsers
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Yahoo Application State Plugin version
  • 4.0.60531.0
  • The plug-in allows you to open and edit files using Microsoft Office applications
  • 2,5,3,1
  • Google Update
  • Wacom Dynamic Link Library
  • Adobe PDF Plug-In For Firefox and Netscape 10.1.0
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.


  • User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:5.0.1) Gecko/20100101 Firefox/5.0.1

More Information

  • Top 10 Contributor
  • Moderator
3193 solutions 24379 answers


If you are using a version of Firefox other than the English / United States version, you may need to install a spell check dictionary. If you already installed the correct dictionary for your localized version in a previous version of Firefox, maybe it didn't get updated after 5.0.1 was installed.

You can re-install that dictionary from here: