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We get the following message: "A copy of Firefox is already open." Nothing running in activity monitor. Looking to keep bookmarks, etc. Mac osx 7.6. Thanks!

VandH
VandH
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I've tried to fix this by addressing .parentlock issue through console and also by removing preference files, but in doing so the latter, lose vital info. I don't have much experience with Terminal. I put all files back in their original places until I know what I'm doing. I've also read we can turn on invisible files and look for the parentlock file that's evidently the culprit. No luck finding that, however. It sounds like there are different options to fix this problem. I'm looking for the safest! Can you help point me in the right direction we don't lose our bookmarks, passwords, etc.? Thanks in advance! The machine is a macbook pro running os 7.6. It's not the machine I'm contacting you through. Vince

I've tried to fix this by addressing .parentlock issue through console and also by removing preference files, but in doing so the latter, lose vital info. I don't have much experience with Terminal. I put all files back in their original places until I know what I'm doing. I've also read we can turn on invisible files and look for the parentlock file that's evidently the culprit. No luck finding that, however. It sounds like there are different options to fix this problem. I'm looking for the safest! Can you help point me in the right direction we don't lose our bookmarks, passwords, etc.? Thanks in advance! The machine is a macbook pro running os 7.6. It's not the machine I'm contacting you through. Vince

All Replies (2)

FredMcD
FredMcD
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https://support.mozilla.org/en-US/kb/update-firefox-latest-version?cache=no Update Firefox to the latest version 55.0.2

Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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VandH said

The machine is a macbook pro running os 7.6.

Do you mean OSX 10.7.6? Only older versions of Firefox run on that OS version, as set forth in this article: Firefox support has ended for Mac OS X 10.6, 10.7 and 10.8.

You could try creating a new profile as a starting point: Profile Manager - Create, remove or switch Firefox profiles. Although that title mentions removing profiles, please don't remove anything until you are successfully back in operation.