My understanding is when sending mass email, you can specify the emails by specifying appropriate targetIDs.

You can also set the whatIds() but does this mean that every recipient will receive the same whatIds()?

How do you send different whatIds() to each recipient?

Attribution to: dublintech

Possible Suggestion/Solution #1

Each entry in the whatIds list matches an entry in the targetObjectIds. This means that each recipient will receive an email containing merge fields from a single whatId specific to them.

You can't send multiple whatIds to a single recipient - its a one to one relationship.

Attribution to: Bob Buzzard
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