Hi Bryan, were you installing the older browser add-on (https://fpn.firefox.com/) or the newer Mozilla VPN software (https://vpn.mozilla.org/) ? ''Mozilla VPN'' Your Firefox says it is running on 64-bit Windows 10, so the Mozilla VPN should be compatible with your system. If you started the installer from the Downloads list, try starting it from File Explorer instead: on the downloads list, click the disk icon on the right to launch File Explorer with the installer selected, and you can press Enter or double-click it to run it from there. Any difference? If that gives the same error, someone might need to dig into what those codes mean (I don't recall seeing a help article on that).