MSI 1921 and 1923: Service Could Not Be Stopped or Installed by the Setup
Error 1921 and 1923 mean a leftover security agent is guarding its own service. Remove the old product with its vendor tool, then install the new agent.
Windows Firewall error 0x80070424: the service is missing or will not start
Error 0x80070424 usually follows a security suite that removed the firewall service. Restore the service and run one properly licensed endpoint tool.