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My desktop will not accept the latest Firefox update and I get a message that another copy of Firefox must be open????

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  • Last reply by cor-el

Geezer79
Geezer79
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I click on the Firefox icon to open it. The program attempt to update before opening. Updating fails. Message says, "Another copy of firefox must be open. Close it and try again." A second copy is not open or at least not one that I'm aware of. I can use the program by saying no to the request to update.

I click on the Firefox icon to open it. The program attempt to update before opening. Updating fails. Message says, "Another copy of firefox must be open. Close it and try again." A second copy is not open or at least not one that I'm aware of. I can use the program by saying no to the request to update.

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cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Run the Firefox program once as Administrator (right-click: Run as Administrator).

If that doesn't solve the problem then do a clean reinstall and remove the Firefox program folder.

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 (not in the Firefox program 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.