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Downloaded firefox 5.0.1 last night, worked fine, Turned computer on today, Mozilla Firefox, it won't start. Get error message, Error: Platform version '5.0' is not compatible with minVersion >=5.0.1 maxVersion <=5.0.1" What do I need to do to fix it?

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  • Last reply by cor-el

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We downloaded firefox 5.0.1 last night, began working with it. It did fine. After about an hour, I turned off my computer. When I turned on my computer, I click on Mozilla Firefox and it won't start. I get this error message, " Error: Platform version '5.0' is not compatible with minVersion >=5.0.1 maxVersion <=5.0.1" from XUL Runner. What do I need to do to fix it?

We downloaded firefox 5.0.1 last night, began working with it. It did fine. After about an hour, I turned off my computer. When I turned on my computer, I click on Mozilla Firefox and it won't start. I get this error message, " Error: Platform version '5.0' is not compatible with minVersion >=5.0.1 maxVersion <=5.0.1" from XUL Runner. What do I need to do to fix it?

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The updater wasn't able to update all the files and some were left as older versions.
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.