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New version of Firefox won't run

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  • Last reply by cor-el

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I updated from an earlier version (using Firefox Setup 2.0.0.14) to the latest version (using Firefox Setup 9.0.1) but then Firefox wouldn't run. (It ran in the background, but no window would open.) I tried several times, including a complete uninstall with deleting all personal data and Firefox-related folders etc. and then a new install. Finally, I decided to reinstall the older version and now Firefox works fine again. Windows Vista.

I updated from an earlier version (using Firefox Setup 2.0.0.14) to the latest version (using Firefox Setup 9.0.1) but then Firefox wouldn't run. (It ran in the background, but no window would open.) I tried several times, including a complete uninstall with deleting all personal data and Firefox-related folders etc. and then a new install. Finally, I decided to reinstall the older version and now Firefox works fine again. Windows Vista.

All Replies (2)

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If you cannot get version 9.0.1 to run, you should be at least able to run version 3.6.25. You can get that here:

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A possible cause is security software (firewall) that blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.

See: