What is the name of the email service platform by Novell NetWare that stores messages in proprietary databases?

The email service platform by Novell NetWare that stores messages in proprietary databases is called GroupWise. This solution was developed to provide email, calendaring, task management, and other collaborative features in a unified interface, specifically targeting enterprise environments. GroupWise uses a unique database structure to store messages, which enhances its organization and retrieval capabilities compared to more traditional mail systems. This proprietary data management approach allows for advanced features such as email threading and enhanced security.

The other options do not accurately represent Novell's email service. NovelWise and GroupSmart do not exist as recognized email platforms, while Yesware is a tool designed primarily for sales professionals that helps with email tracking and productivity but is not affiliated with Novell NetWare or its messaging services. Thus, GroupWise stands out as the correct answer given its established role in Novell's suite of enterprise communication solutions.