What does the Email Duplicate ID field contain?

The Email Duplicate ID field contains a unique identifier that is generated specifically for emails that are considered duplicates. This means that when an email system identifies multiple instances of the same email being sent or received, it assigns a unique ID to all of these duplicate messages. This allows the system to track which emails are duplicates and ensures accurate handling, such as during processing or organization.

By utilizing this unique identifier only for duplicates, the system avoids confusion among non-duplicate messages. In contrast, other options, such as a unique identifier for all emails or the sender's email address and subject line, do not specifically pertain to the functionality of the Email Duplicate ID field, which is strictly focused on helping manage and recognize duplicates distinctively.