Encryptomatic OpenPGP vs gpg4o

Encryptomatic OpenPGP is a Windows application for encrypting and signing messages and files, with Outlook integration. Encryption happens locally on the PC, and messages remain protected end-to-end from sender to recipient; recipients need OpenPGP software to decrypt them. Files can also be encrypted or signed from the Windows right-click context menu. The software supports Windows 10 and 11, plus listed Classic Outlook versions from 2013 through Microsoft 365 in 32-bit or 64-bit editions. PGP key-server support covers key sharing, discovery, and revocation, including MIT.EDU. Administrators can customize the interface and deploy through MSI silent installation and registration; some shared environments can use activation-free enterprise versions. Personal users, nonprofits, activists, and individual journalists can use it free, while for-profit business domains require a license. Business and free editions have identical encryption capabilities. Business pricing starts at $29.99 a year for one license; Mac is not supported.

gpg4o is a Microsoft Outlook add-in for encrypting, decrypting, signing, and checking messages and attachments. It uses public and private keys under the OpenPGP standard, and supports encrypted HTML email, PGP/MIME, and PGP/Inline. Its key management can synchronize keys, use local or public key servers, and check the Web of Trust; central management requires Enterprise KeyServer. The product also supports terminal servers, Microsoft Policy Manager, automatic key generation, and working groups. When encryption is enabled, it protects message text and attachments, but not the subject line or recipient list. The current feature page lists Outlook 2024 or 365 Classic on Windows 11 and marks Mac OS unsupported. A limited free version is available without a time limit, and a 180-day trial is noted. The listed gpg4o plan costs €99.95 a month. After maintenance expires, users can still send and read encrypted or signed email, but they do not receive further updates.