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After booting my computer, when opening FireFox, a message pops up saying that the FireFox process is already open.

  • 4 replies
  • 1 has this problem
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  • Last reply by wkwkwkwk1

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It happens after booting my computer, so the process can't be running. I also checked it on task manager. I tried changing "Read-Only" status, but when I open properties again, even before trying to open FF, it's again "Read-Only".

Thanks in advance, wkwkwkwk1

It happens after booting my computer, so the process can't be running. I also checked it on task manager. I tried changing "Read-Only" status, but when I open properties again, even before trying to open FF, it's again "Read-Only". Thanks in advance, wkwkwkwk1

Chosen solution

Type %APPDATA% in your Run Box > open Mozilla folder > open Firefox folder > which contains the profiles.ini file (see screenshot how looks like) and rename it to profiles.iniOLD then the next time you start Firefox it will open with a new default profile, just as though you installed Firefox for the first time.

see for more info : Creating a new default profile

see also : Transferring data to a new profile - Firefox


thanks again

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Hello wkwkwkwk1, try to delete the parent.lock file in profile folder and check it again, see for more information: Remove the profile lock file.


thank you

Modified by ideato

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I'm sorry, but that doesn't work as well, since that file doesn't exist, therefore it can't be deleted. I also tried uninstalling and re-installing.

Thanks the same, wkwkwkwk1

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Chosen Solution

Type %APPDATA% in your Run Box > open Mozilla folder > open Firefox folder > which contains the profiles.ini file (see screenshot how looks like) and rename it to profiles.iniOLD then the next time you start Firefox it will open with a new default profile, just as though you installed Firefox for the first time.

see for more info : Creating a new default profile

see also : Transferring data to a new profile - Firefox


thanks again

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Like a charm! Pity I lost FF looks...but thanks!