This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

This thread was archived. Please ask a new question if you need help.

When I try to open FireFox it says I am missing nspr4.dll and mozqlite3.dll. How do I fix this?

  • 1 reply
  • 5 have this problem
  • 7 views
  • Last reply by cor-el

ianzhofer
ianzhofer
more options

I downloaded FireFox 8.0 not too long ago, and when I launched it, it said nspr4.dll and mozqlite3.dll were not found on my computer. I've used FireFox for a long time, and this has never happened before.

I downloaded FireFox 8.0 not too long ago, and when I launched it, it said nspr4.dll and mozqlite3.dll were not found on my computer. I've used FireFox for a long time, and this has never happened before.

All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

Do a clean (re)install and delete the Firefox program folder (C:\Program Files\Mozilla Firefox\).

Download a fresh Firefox copy and save the file to the desktop.

Uninstall your current Firefox version if possible.

  • Do not remove personal data when you uninstall the current version or you lose your bookmarks and other data in the profile folder.

Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

  • It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.

Your bookmarks and other profile data are stored elsewhere in the Firefox Profile Folder and won't be affected by a reinstall, but make sure that you do not select to remove personal data if you uninstall Firefox.