Do you have an "Old Firefox Data" folder on the desktop? *https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile ---- You can check for problems with the profiles.ini file that registers profiles. You can find the profiles.ini file in this hidden location: *Windows: %AppData%\Mozilla\Firefox\<br>C:\Users\&lt;user&gt;\AppData\Roaming\Mozilla\Firefox\ See: *https://support.mozilla.org/fr/kb/how-run-firefox-when-profile-missing-inaccessible You can try these steps: *delete the profiles.ini file to make Firefox create a new (default) profile *use the Profile Manager to create a new profile<br>https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles *register an orphaned profile that isn't listed in the Profile Manager You can check if you have an orphaned profile that isn't registered in profiles.ini and that doesn't show in the Firefox Profile Manager. You can check that by opening the current profile folder via the <b>about:profiles</b> page and go up one level (..) to see if there are unlisted profiles present. If you have found an orphaned profile then you may want to recover some personal data or restore his profile. *https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile You can recover an orphaned profile via these steps: *use the Profile Manager to create a new profile<br>https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles *click "Choose Folder" in the Profile Manager *browse to the location of this profile to register this profile in the Profile Manager and use this profile See "Profile was moved or renamed": *https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible Note that you should never use "Choose Folder" to specify a folder that already contains files that do not belong to Firefox. Only use "Choose Folder" to recover an profile that isn't listed in the Profile Manager.

   delete the profiles.ini file to make Firefox create a new (default) profile
   use the Profile Manager to create a new profile
   https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles 

Hello, Thank a lot, I had 2 profiles, I delete the first one and I use the last one. I used the following way : You can try these steps: delete the profiles.ini file to make Firefox create a new (default) profile use the Profile Manager to create a new profile https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles I restarted my computer and I launch the profile manager windows : Firefox (32-bit) on 32-bit Windows (or 64-bit Firefox on 64-bit Windows) •"C:\Program Files\Mozilla Firefox\firefox.exe" -P Best regards Pascal