Kaspersky Plus cannot activate the Firefox add on

[noone]

Edition    Windows 11 Pro
Version    24H2
Installed on    ‎5/‎31/‎2025
OS build    26100.4946
Experience    Windows Feature Experience Pack 1000.26100.197.0

 i cannot activate the kaspersky extention of Firefox no matter what i did

Edited 4 hours ago by noone
screenshot

[Flood and Flood's wife]

3 hours ago, noone said:

Edition    Windows 11 Pro
Version    24H2
Installed on    ‎5/‎31/‎2025
OS build    26100.4946
Experience    Windows Feature Experience Pack 1000.26100.197.0

 i cannot activate the Kaspersky extension of Firefox no matter what i did

Hello @noone, 

Welcome!

Additional resources: 

• How to install the extension in Mozilla Firefox
• How to enable the extension in Mozilla Firefox

1. Is FireFox, basic, standard FF, current version 141.0.3 - no FF derivatives? 
2. Which Kaspersky Plus *version* is installed, on Windows Taskbar, *Hidden icons*, rightclick the Kaspersky icon, select About? 
3. Have (you) tried installing / activating https://addons.mozilla.org/en-US/firefox/addon/kaspersky-protection-2021/ *without* Windows Feature Experience Pack 1000.26100.197.0?
4. IF 'no', please do, remove the FEP, reboot, retry installing / activating the FF extension?
5. IF the extension works without FEP, (you) can reinstall FEP, if the extension continues to work -> good, if the extension stops working, please read & follow: What to do if you experience issues -> submit a request to Kaspersky Customer Service.

Please share the outcome with the Community when it's available? 

Thank you🙏
Flood🐳+🐋

Edited 57 minutes ago by Flood and Flood's wife
added additional resources