preventing duplicate emails in office 365

Use of antivirus software with the email scanning feature enabled.

Multiple POP3 mailboxes configured to use the same PST data file.

Messages are duplicated when receiving, sending, or synchronizing.

Work with a single mailbox on more than one device.

When you work in this mode, tasks, calendars, and sent messages may be duplicated.

Running multiple copies of Outlook on the same computer at the same time.

Backup copies of messages are duplicated with existing ones. Copying the same data will create duplicates.

Importing messages and other Outlook items from files or merging multiple PST files into one.

If the 'Leave messages on the server' option is enabled, the messages you have already received are being downloaded again.

Interruptions when downloading messages from POP3 mailboxes.

Different rules that work with incoming or outgoing mail can copy the same message to different folders.

In this case, there may be server synchronization failures, which results in duplicates. Repeated synchronization attempts can create duplicates.

Mobile device sync errors with the desktop version of Outlook.

These are the most common reasons cause of duplicates in Outlook: Duplicate contacts appear when you copy and import them, while duplicate tasks, appointments, and meetings appear when multiple users or multiple Outlook windows work with the same Outlook items at the same time. Duplicate emails can appear when you receive or send a message. This may be due to incorrect settings, technical failures, or user errors.

There are many situations where messages get duplicated in Outlook folders. Remove the duplicates and make sure that they no longer appear. Read this article and find out where the duplicate messages, contacts, tasks, reminders, and Outlook calendar items appear from. In addition, many duplicates significantly increase the search time in Outlook, and the search results will consist of a large number of redundant items that are difficult to work with. A large number of duplicates increases the size of your mailbox, taking up extra space on your disk and on the server. Having duplicates causes confusion and can be a waste of time when you read and send an email. If you use Microsoft Outlook, you will definitely encounter duplicates.

Preventing duplicate emails in office 365