Windows 10 reached EOS (end of support) on October 14, 2025. For more information, see this article.

Avatar for Username

Hilfe durchsuchen

Vorsicht vor Support-Betrug: Wir fordern Sie niemals auf, eine Telefonnummer anzurufen, eine SMS an eine Telefonnummer zu senden oder persönliche Daten preiszugeben. Bitte melden Sie verdächtige Aktivitäten über die Funktion „Missbrauch melden“.

Weitere Informationen

Dieses Thema wurde archiviert. Bitte stellen Sie eine neue Frage, wenn Sie Hilfe benötigen.

<Add-on> could not be installed because Firefox cannot modify the necessary file.

  • 1 Antwort
  • 10 haben dieses Problem
  • 12 Aufrufe
  • Letzte Antwort von cor-el

switch
switch
Weitere Optionen

I see that for the issue:

<Add-on> could not be installed because Firefox cannot modify the necessary file.

The usual fixes include: - ensuring that xpinstall.enabled is set to true - ensuring that extensions.alwaysUnpack is set to true

What might be the non-usual fixes as I have set both to true and I still get the message above.

I have tried installing the <add-on> after I have set the values to true, then again after restarting my browser, then again after restarting my computer and finally tried creating a new profile and repeated each of the steps after setting the 2 preferences to true.

I see that for the issue: <Add-on> could not be installed because Firefox cannot modify the necessary file. The usual fixes include: - ensuring that xpinstall.enabled is set to true - ensuring that extensions.alwaysUnpack is set to true What might be the non-usual fixes as I have set both to true and I still get the message above. I have tried installing the <add-on> after I have set the values to true, then again after restarting my browser, then again after restarting my computer and finally tried creating a new profile and repeated each of the steps after setting the 2 preferences to true.

Alle Antworten (1)

cor-el
cor-el
  • Moderator
Weitere Optionen

Can you at least update to the latest Firefox 10.0.10 ESR version?

Firefox 10.0.x ESR:

So a new profile with no other extensions didn't work as well?

Which extension is causing this problem or can't you install any extensions at all?