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Firefox 5.0 wont start up after new update.

  • 3 replies
  • 1 has this problem
  • 4 views
  • Last reply by Pengull

Pengull
Pengull
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Pop up says "This application has failed to start because xul. dll was not found. Re-installing the appliction may fix this problem." I now have to use Firefox 3.6.13 and I have no problem with it.

UPDATE! Its fixed now

Pop up says "This application has failed to start because xul. dll was not found. Re-installing the appliction may fix this problem." I now have to use Firefox 3.6.13 and I have no problem with it. UPDATE! Its fixed now

Modified by Pengull

All Replies (3)

foxyshadis
foxyshadis
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Did you try to download and install again? It might have been corrupted.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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You need to do a clean reinstall.

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

  • Uninstall your current Firefox version.
  • Do not remove personal data when you uninstall the current version.

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.

Pengull
Pengull Question owner
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What I did before anyone had replied was get all the updates for my old Firefox and then it upgraded it to the new Firefox 5. My old Firefox 5 shortcut doesn't work but my new Firefox 5 shortcut does. Then I had uninstalled it and works fine now!