In Folders view
In the Folders view, visual indicators indicate the presence of new messages that have not been processed in a thread.
When a thread contains this orange bubble with a number, there are new messages to be processed. The number indicates how many new messages are in this thread. These messages are identifiable by the “New” status displayed at the top right of the message frame.
In Tasks view
In Tasks view, a task containing new messages is displayed in blue.
If there are no messages in a task, the task is displayed in grey.