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– When the wizard asks for a profile folder, browse to the copied folder, ie. – create a new profile, call it “default” – rename the old profile to “profile.save” Windows doesn’t copy the “parent.lock”, and another file, because they are “in use”. – I used Explorer to copy the profile folder, within the Profiles folder. No dice – it still thinks the “parent.lock” is in use.
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I created a new profile, and used the browser (in the wizard) to make it point to the old profile. So I opened up a DOS shell, cd’d to C:Program FilesMozilla Firefox and ran “firefox.exe -profilemanager”. Windows prevents it, saying that it’s in use (even though Firefox is not in the task manager). I found the parent.lock file in C:Users\AppDataRoamingMozillaFirefoxProfiles, and tried to delete it. Rebooting always fixed it, but I’d had enough, and wanted to fix it without rebooting. I had the problem (frequently) with Vista. I haven’t had this happen before today, but it can happen if (for example) someone turns your computer off while Firefox is running. Under Unix/Linux, you’ll need to remove two files “lock” and “.parentlock”. This page tells you what the lock files are for Firefox on Windows/Linux/Mac. Ubuntu), it will be at ~/.mozilla/firefox//. This page tells you how to find the location of your Firefox profile. For example, on Linux the command “ps auxThat happened to me today, surprise surprise 🙂 Here’s how to fix the deeper problem: Usually, you can just kill the firefox process to solve this problem. To open a new window, you must first close the existing Firefox process, or restart your system. The message looks like this:įirefox is already running, but is not responding. Sometimes when you try to start Firefox, it warns you that Firefox is already running.
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