Alternativas ao Netrepid Hosted Exchange Services para VirtualBox com licença de código aberto

• VirtualBox
  Todas as plataformas Windows Mac Linux Android iPhone iPad Android Tablet Web Self-Hosted Software as a Service (SaaS) BSD Microsoft Office Outlook Thunderbird VMware vSphere Hypervisor Cloudron OpenPGP VirtualBox
• Licença Open Source
  Qualquer licença Licença gratuita Licença Open Source Licença comercial