Keeley Companies

KB Article:  Duplicate emails

Date: 5/2/2024

Author: Brian C Burrus   

Summary: User Experiencing issue with multiple emails coming from outside email source              

Ticket reference: #INC - 316107

Resolution:

Top reasons why duplicate email problems occur in MS Outlook.

There are multiple reasons behind duplicate emails that might be sent or received in Outlook. Below listed are the top reasons that are explained one by one.

1. Sender is incorrectly sending to multiple accounts. Verify
2. Synchronizing Outlook email on multiple devices

It is a common practice of many Outlook users to use the same Outlook profile on multiple devices like desktops, laptops, tablets, and mobiles, which ultimately leads to the creation of multiple copies or duplicates of emails.  Logout of all devices except one and allow 15-20 minutes for one device to sync. You can resolve this by manually deleting emails one by one.

Mostly, Outlook users configure their personal as well as professional email together. They work separately being in one place which obviously helps in increasing productivity. But it becomes a bit confusing, so make sure the accounts are separate indeed and are not showing as aliases for the one Outlook account. If you are using aliases, the single mailbox might get set up twice, leading to duplicate Outlook emails.

Another common cause of getting duplicate emails in Outlook is having multiple folders set up for storing your messages. For example, if you have an Inbox folder and a Sent Items folder, each time you send an email, a copy of the message will be stored in both folders. This can lead to duplicates appearing in your inbox when you view your email from either folder.

MS Outlook generates duplicates for every Send/Receive cycle due to the account settings; the checkbox “Leave a copy of the messages on the server” has been enabled. You can fix this by disabling the Account Setting in all the MS Outlook versions.

Duplicate emails can also appear if you have set up Outlook to download messages from another email account, such as a POP3 account. When you do this, each time you receive an email in the other account, a copy of the message is also downloaded and stored in Outlook. In Outlook, you can see duplicate emails in your inbox because of this issue.

Users archive emails to PST files for backup or exporting data. If you import any of the PST files to the same Outlook profile from which it was exported, it will create duplicates for complete mailbox data items.

A simple mistake in your configuration may be causing issues, especially when dealing with incoming email messages. Incorrect rules might be the reason behind the duplicate data in your Outlook mailbox. It’s essential to review and adjust your rules to ensure they are set up correctly and avoid this messy situation. Check Rules that copy the email twice or if auto-reply is on.

The issue of duplicate Outlook emails can also occur when Outlook is set up to automatically archive messages. Whenever you receive a new email in Outlook, a copy of that message is also saved in an archive file. If you look at your email archive from the inbox, duplicates may appear.

Another reason for duplicate emails in Outlook could be due to a virus or malware attack. Viruses and malware can cause Outlook to act abnormally and create duplicate emails. To fix this issue, you should run a scan on your computer to detect and remove any viruses or malware. Antivirus software can help you to detect and remove any malicious software on your computer.

OST/PST files are important files that contain all your Outlook data including emails, contacts, and calendar data. If these files are corrupted, it can lead to duplicate emails in Outlook. To fix this issue, you can repair the OST/PST files using the Scanpst.exe tool. This inbox repair tool is a built-in tool that comes with Outlook and can fix minor issues with OST/PST files.