All of your personal settings, bookmarks, and other information are kept in your Firefox profile. Firefox needs an unlocked profile to start up, and if the profile is locked, it displays the message, Firefox is already running, but is not responding. This article explains what to do if you see this message and how to prevent it from showing at startup.
End Firefox processes :
If Firefox did not shut down normally when you last used it, Firefox might still be running in the background, even though it is not visible.
If you try to open it while it’s running, an error message will appear with the option to click Close Firefox. If that doesn’t solve the problem, restart your computer or try the following options.
Use the Windows Task Manager to close the existing Firefox process :
- Right-click on an empty spot in the Windows task bar and select Task Manager (or press Ctrl+Shift+Esc).
- When the Windows Task Manager opens, select the Processes tab.
- Select the entry for firefox.exe (press F on the keyboard to find it) and click End Process.
- Click Yes in the “Task Manager Warning” dialog that appears.
- Repeat the above steps to end any additional firefox.exe process, if more than one entry is found, then exit the Windows Task Manager.
- Start Firefox normally.
Initialize the connection to a file share :
If you store the profile on a file share, try accessing the file share beforehand using Windows Explorer.
Check access rights :
Firefox must also have the right to create files in the profile folder. The error can occur if you try to use a profile from a file system mounted with read-only permission (e.g. a remote Windows share which doesn’t have “Allow network users to change my files” checked).
To check if the profile folder has the proper permissions:
- Go to your Firefox profile folder.
- Go up one folder.
- Right-click on your profile folder and select Properties.
- Click on the General tab.
- Make sure Read-only is not checked marked.
Restore data from a locked profile :
If you are unable to unlock the profile using the above methods, use the Profile Manager to create a new profile and migrate your data from the locked profile to the new profile.