Design a Scalable Email Service

Design an email service capable of handling high volumes of email sending and receiving, ensuring deliverability, and managing email-related tasks efficiently. The system should support features like email composition, delivery status tracking, spam detection, and automated responses. Scalability is critical to accommodate fluctuating volumes, and the architecture should include load balancing, distributed processing, and storage solutions. Additionally, the system must ensure high availability, data security, and compliance with email sending standards and regulations.