Solution: Check the Task Manager to ensure you have only one outlook.exe running while synching. Synchronization failures and errors lead to duplicate emails in Outlook. When working in the same Outlook profile on different devices, such as desktop, tablet or mobile phone, messages are often synchronized multiple times. Synching Outlook account on multiple devices. Activate the stop processing more rules action for those rules that result in duplicate emails in Outlook when applying together. Solution: Check your Outlook rules to ensure that you haven't any rule combination that causes duplicates in your Inbox.

Those can be several 'Move the item to folder' rules, plus others. For each incoming message, Microsoft Outlook applies all the rules together. One of the most common causes of duplicate emails in an Outlook mailbox is the rule configuration. Here is the list of the 7 situations that provoke repeated emails in Outlook and the ways to avoid the problem. The reasons that may cause email duplicating in Outlook may be different. Why Outlook duplicates emails and how to prevent the email duplicating Removes duplicate Outlook emails in bulk and by schedule with command line app.Allows setting your own criteria to specify what messages are duplicates.Removes duplicate emails in Outlook PST data files.Deletes duplicate Outlook emails from one or multiple folders at once.Enables moving duplicate messages to the specified Outlook folder, to bring them back to their original locations, if necessary.Removes duplicate emails in Outlook folders, Exchange and Office 365 mailboxes, as well as Exchange Server public folders.

Delete duplicates in outlook