- Still check STARTTLS when reverse DNS lookup fails - Disable STARTTLS/TLS checks when running on Windows to avoid `timeout_decorator` [Windows incompatibility](https://github.com/pnpnpn/timeout-decorator/issues/1)
4.1.7
-----
- Better DNS exception handling - Show errors instead of warnings when checking NS and MX records for non-existent domains
4.1.6
-----
- Fix TLS/STARTTLS failure output
4.1.5
-----
- Add warning if MX hosts are missing A or AAAA records