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Problem updating from v12 to v14

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  • Last reply by cor-el

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Running Windows 7 64 bit. I tried to update from Firefox v12 to v14 when the pop-up appeared, however the update failed each time. I then removed v12 via Control Panel and then installed v14.0.1. v14 will not run. I get an error message from XUL Runner Error: Platform version '12.0' is not compatible with miniVersion>=14.0.1 maxVersion<=14.0.1

Running Windows 7 64 bit. I tried to update from Firefox v12 to v14 when the pop-up appeared, however the update failed each time. I then removed v12 via Control Panel and then installed v14.0.1. v14 will not run. I get an error message from XUL Runner Error: Platform version '12.0' is not compatible with miniVersion>=14.0.1 maxVersion<=14.0.1

Chosen solution

You're welcome

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All Replies (9)

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According to your system details, you posted your question using Firefox 14.0.1, so I assume Firefox starts ok; you just got that error message?

There is a malicious extension called XULRunner 1.9.1. Maybe that's what is giving you the error. If that's it, go to Firefox > Add-ons > Extensions, and beside XULRunner, click Remove.

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See:

This issue is usually caused because some files weren't updated properly by the updater.

Do a clean reinstall and delete the Firefox program folder (C:\Program Files\Mozilla Firefox\) before reinstalling a fresh copy of 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 your current Firefox version, because all profile folders will be removed and you will also lose your personal data like bookmarks and passwords from profiles of other Firefox versions.

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

Your bookmarks and other profile data are stored in the Firefox Profile Folder and won't be affected by an uninstall and (re)install, but make sure that "remove personal data" is NOT selected when you uninstall Firefox.


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No, Firefox v14 won't even start.

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Tried the clean install as suggested but still Firefox 14 will not run and the same error message comes up

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You did delete the entire Firefox program folder (especially application.ini)?

Which security software (firewall, anti-virus) do you have?

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Yes, deleted the Mozilla Folders completely.

Zonealarm Extreme Security.

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If you use ZoneAlarm Extreme Security then disable Virtualization and reinstall Firefox. Other security software may have similar features to prevent Firefox from updating files properly.

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Thanks for the help. Disabling virtualization of Zonealarm was the answer.

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Chosen Solution

You're welcome