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I am trying to upgrade to Firefox 4, but my computer says the program is already in use.

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  • Last reply by cor-el

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I am running Firefox 3.6.17 on my Mac (OS 10.6.7), and I've downloaded Firefox 4, but when I try to drag the Firefox icon to the applications folder, it tells me an older item with this name already exists. When I tell it to overwrite this file, it says it can't because the file is in use, even though Firefox isn't running.

I am running Firefox 3.6.17 on my Mac (OS 10.6.7), and I've downloaded Firefox 4, but when I try to drag the Firefox icon to the applications folder, it tells me an older item with this name already exists. When I tell it to overwrite this file, it says it can't because the file is in use, even though Firefox isn't running.

Chosen solution

If you get an error message that you do not have sufficient permissions or have other problems with updating to update then easiest is to download the full version and trash the currently installed version to do a clean install of the new version.

Download a new copy of the Firefox program and save the DMG file to the desktop

  • Trash the current Firefox application to do a clean (re-)install
  • Install the new version that you have downloaded

Your profile data is stored elsewhere in the Firefox Profile Folder, so you won't lose your bookmarks and other personal data.

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Chosen Solution

If you get an error message that you do not have sufficient permissions or have other problems with updating to update then easiest is to download the full version and trash the currently installed version to do a clean install of the new version.

Download a new copy of the Firefox program and save the DMG file to the desktop

  • Trash the current Firefox application to do a clean (re-)install
  • Install the new version that you have downloaded

Your profile data is stored elsewhere in the Firefox Profile Folder, so you won't lose your bookmarks and other personal data.

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That fixed it and retained my bookmarks, preferences, etc. Thanks!

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You're welcome