Reply To: How to Remove Duplicate Emails in Office 365? Barry Alllen ~ Modified: September 29th, 2016 ~ ~ 1 Minute Reading Home › Forums › How to Remove Duplicate Emails in Office 365? › Reply To: How to Remove Duplicate Emails in Office 365? September 29, 2016 at 5:03 am #3532 Score: 0 Barry AlllenModerator Karma: 25 pts Hi, You should probably take backup of the emails and then delete all the duplicate emails from your mailbox. To know more about how to go forward with deleting duplicate emails in O365, please follow the link below: Delete Duplicate Emails in Office 365 Search