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firefox is already running but its not

  • 4 replies
  • 10 have this problem
  • 11 views
  • Last reply by cltutwiler

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I booted my computer and tried to open firefox but a windows pops up and say Firefox is already running, but not responding. To open a new window you must close and existing windows and try again.

The problem is it isn't running. I open my task manager and there is no programs running, I check running processes and nothing to do with Mozilla firefox is in there. How can it already be running if it isn't open?

I booted my computer and tried to open firefox but a windows pops up and say Firefox is already running, but not responding. To open a new window you must close and existing windows and try again. The problem is it isn't running. I open my task manager and there is no programs running, I check running processes and nothing to do with Mozilla firefox is in there. How can it already be running if it isn't open?

Chosen solution

I actually fixed it. I was looking in c:\users/myname/appdata/local/mozilla/firefox/profiles

I looked in c:\users/myname/appdata/roaming/mozilla/firefox/profiles and found the profile.locked file and deleted it. Works great again.

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All Replies (4)

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Did you check the whole list? Sometimes the list is not alphabetical. If you still have trouble, go to Mozilla.org for the full install.

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Yes I checked the entire list. I even selected to show processes for all users and there is nothing in there about Mozilla. I uninstalled the program and selected to uninstall preferences and profiles too so there was no trace of Mozilla on my computer. I then reinstalled it and same issue. Not sure what you mean go to mozllia.org for the full install?

I included an image of the error and my open processes. You will see Mozilla firefox in the processes but as soon as I click OK on the error box and the process closes.

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Mozilla.org is a link to where Firefox can be downloaded from.

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Chosen Solution

I actually fixed it. I was looking in c:\users/myname/appdata/local/mozilla/firefox/profiles

I looked in c:\users/myname/appdata/roaming/mozilla/firefox/profiles and found the profile.locked file and deleted it. Works great again.