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A copy of Firefox is already open. Only one copy of Firefox can be open at a time. I cannot find the open one. was having some problems. deleted and trying to re-install. I get this message each time

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  • Last reply by drmajor

drmajor
drmajor
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Some web pages did not load correctly. (on Imac). Deleted Firefox and moved Profile to another drive to backup. Downloaded new Firefox. When I try to install, I keep getting this message-"A copy of Firefox is already open. Only one copy of Firefox can be open at a time." I went in and searched for all occurrences of Firefox or Mozilla and deleted.

It will still not load.

Some web pages did not load correctly. (on Imac). Deleted Firefox and moved Profile to another drive to backup. Downloaded new Firefox. When I try to install, I keep getting this message-"A copy of Firefox is already open. Only one copy of Firefox can be open at a time." I went in and searched for all occurrences of Firefox or Mozilla and deleted. It will still not load.

All Replies (2)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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See:

Create a new profile as a test to check if your current profile is causing the problems.

See "Basic Troubleshooting: Make a new profile":

If that new profile works then you can transfer some files from the old profile to that new profile, but be careful not to copy corrupted files.

See:

drmajor
drmajor Question owner
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I cannot get Firefox to run now. I backed up my Profile to another drive. Cannot create a new one as Firefox will not run. It says there is another copy running. However, I have deleted all Firefox and Mozilla files and downloaded new. When I try to run it, I get the message to close Firefox as two cannot run at once.

I did create a new Mac account logon and can run Firefox there, so something in the other account is showing Firefox is running.

I also checked in ACTIVITY MONITOR and in SETUP and there is no Firefox or Mozilla running.

So, where can this bug be hiding????