How to remove redundant messages by “Clean Up Conversation” in Outlook 2013?

“Clean Up Conversation” helps to evaluate the contents of each message in the Conversation. If a message is completely contained within one of the replies, this message will be deleted.

1. Go to “Home” tab, in the “Delete” group, click “Clean Up”.
   
2. Choose one of the following:

• “Clean Up Conversation” – to review and delete redundant messages of the current conversation.
• “Clean Up Folder” – to review all conversations in the selected folder and delete redundant messages.
• “Clean Up Folder & subfolders” – to review all conversations in the selected folder and related folder and delete redundant messages.