Gpg4win vs Secure Message

Gpg4win has no write-up on Specifiction yet; its figures are above.

Secure Message is a self-hosted inbound email gateway that filters mail before it reaches an existing mail server. Its Community features include Postfix content filtering, spam scoring, DNSBL, SPF, DKIM and DMARC checks, quarantine, mail logs and administrator MFA. Professional adds a recipient web portal: recipients open protected messages with a one-time code, without an account or app. Its rules can encrypt, redirect or block sensitive outbound messages, and recipient checks can use SMTP callout, LDAP or directory lookups. Stored messages, attachments and quarantine use Fernet encryption with AES-128-CBC and HMAC-SHA256; the key remains on the customer host. Access controls include TOTP administrator MFA, role-based access and audit logging, with logs exportable to CSV. Enterprise adds AI Autopilot tuning, eDiscovery and archive search, DLP and disclaimers; Autopilot and the classifier are off by default. The gateway can sit in front of Microsoft 365 or an existing mail server without mailbox migration. The single-node appliance runs on Debian 13, with 2 vCPU and 4 GB RAM recommended as a starting point.