MetaDefender Email Gateway Security 5.2.1 6. Releases 6.8. Version 5.2.1 6.7. Version 5.2.0 6.6. Version 5.1.1 6.5. Version 5.1.0 6.4. Version 5.0.3 6.3. Version 5.0.2 6.2. Version 5.0.1 6.1. Version 5.0.0