In certain versions of Windows 10, you may receive a notification with a warning about Microsoft-verified apps when you run the Firefox installer.
Any copy of Firefox downloaded from www.mozilla.org is safe to install, so choose "Install anyway".
- You can also download and install Firefox from the Microsoft Store.
- Using Windows 10 in S mode? See Windows 10 S won't let me install Firefox.
If you do not see the option to “Install anyway”, follow the steps below to change your system settings.
- Open the Windows 10 start menu and select Settings.
- Click on Apps in the Windows Settings menu.
- In the Apps & features section go to Choose where to get apps, click on the dropdown menu below and select one of the options that allows you to install from Anywhere.
- Run the Firefox Installer again. Your Windows may now allow it to install Firefox.