Remove Duplicate Outlook Emails

Updated on December 02, 2022 by Savita Sharma

Outlook is well-known for its extensive capabilities and useful functionality. But, when dealing with MS Outlook, many people have the problem of duplicated emails. This complicates mailbox administration, despite the fact that efficient mailbox management is critical due to the loss of critical data held in it. That's why you must focus on quickly clearing duplicate mail in Outlook.

Why Should Outlook Duplicate Emails Be Removed?

Microsoft Outlook is the most widely used email client, so maintaining it operational is critical. Duplicating email items in a mailbox, on the other hand, might degrade its functionality. Aside from this, consumers experience a variety of additional issues, which are described below:

Enhance Inbox Size: If you continue to receive duplicate emails with attachments in Outlook, the volume of your inbox will grow. Furthermore, if the mailbox is too large, the performance suffers.

Message Could Not Be Found: Once you start searching for an email in Outlook using the search function, it shows a full list of messages and takes longer than expected.

Taking Up More Storage: Because the number of duplicate objects grows, it takes up extra storage on the hard disk and increases CPU utilization. Furthermore, it raises the likelihood of losing data.

Common Causes of Outlook Duplicate Emails

There are several common causes of the duplicate email error in Outlook. For the reasons below, be aware of them to prevent future issues.

Creating Multiple Accounts

When a similar email account is configured on numerous platforms, incoming data may be synchronized multiple times. As a result, you may get numerous copies of the same email in Outlook.

Utilization of Third-Party Antivirus Software

Whenever an anti-virus application is installed on a workstation similar to Outlook, it has the potential to interrupt "Send/Receive" requests in Outlook. As a result, when Outlook sends and receives messages, it believes it is connecting with a mail server. However, the email application is connected to the anti-virus scanner. This means that the virus scan solution is in charge of terminating the connection to the mail server.

If somehow the connection is not correctly closed, the email message is not marked as received. This gives you the option of getting the previously received message once more during the next send/receive session.

The time elapsed among sending and receiving is brief.

Whenever the duration between sending and receiving messages is configured for a small period of time, say just under five minutes, you may see email duplication. The issue arises because, while Outlook is executing the attempt to send the first email uploaded to the mail server, the next send/receive procedure begins before the first one is completed.

Some Effective Solutions to Remove Duplicate Outlook Emails?

Actually, you are not the first person who has faced this problem. Many users have faced this error, and that’s why experts have created some effective methods and tools to fix this error. Keep reading this post; you will get informed about all things.

Clean up your inbox.

Microsoft Outlook has a number of programs and add-ins that can assist you in successfully cleaning up duplicate emails in MS Outlook. Clean Up is a built-in function that assists in the removal of duplicated inbox email messages. This activity may be utilized in the following ways:

  • 1. Begin by using Microsoft Outlook.
  • 2. Choose the mailbox directory containing identical emails.
  • 3. Just on the Home tab, select Clean Up. Next, choose one of the following options based on the presence of duplicate items. Manual Steps to Remove Duplicate Outlook Emails
  • 4. The Clean Up Conversation deletes and moves any duplicate email messages from the conversation to the Deleted Items directory.
  • 5. Using the Clean Up Folder, you may eliminate duplicate email messages from a specified directory.
  • 6. The Tidy Folders and Subfolders option will clean up folders and subfolders.
  • 7. Then, right-click the Deleted Items folder and pick the Empty folder feature to completely erase the duplicate email messages.

Set the frequency of inbox updates.

Sometimes, updating the inbox frequency can provide some additional fixes. Increase the frequency of Inbox updates by following the steps below:

  • 1. Launch Outlook and go to the Send or Receive tab.
  • 2. Then, choose "Define Send or Receive Groups."
  • 3. Specify the setting for "Schedule an automated send/receive every" to anything around 15 to 30 minutes max.
  • How to Eliminate Duplicate Emails from MS Outlook

Deactivate Outlook's virus scanner integration.

As previously described, an integrated virus scan solution with Outlook may interrupt Send and Receive requests. This may result in the downloading of duplicate messages.

To overcome this, consult the anti-virus documentation and look for the technique for disabling email security. Wait for the prior Send and Receive rounds to finish after disabling email protection. Then, ensure that duplicate messages are no longer being received and that the anti-virus application is functioning normally.

Make use of Regain Outlook Duplicate Remover Software

The Regain Outlook Duplicate Remover program was created specifically to deal with unwanted duplicates in MS Outlook. The tool has a plethora of options for removing duplicate mail, contacts, events, reminders, and so on from Outlook inboxes.

Simple steps to remove duplicate emails using Regain Outlook Duplicate Remover

  • 1. Firstly, download and install the software.
  • 2. Then, after running, you find the home screen like in the below image.Step 1
  • 3. Browse and select the Outlook PST files to scan.Step 2
  • 4. Get an overview of items with duplicate numbers.
  • Step 3
  • 5. Choose Remove Duplicate Items option and just save it.

Regain Outlook Duplicate Remover - Software Features:

  • Embedded with an advanced algorithm that searches duplicate items, contained by same folder or the entire selected folders automatically.
  • Easily removes duplicate contacts, emails, attachments, calendars, notes, tasks, etc. from multiple folders of Outlook without slowing down the performance.
  • Various Options to Remove Duplicate Items such as - Delete Permanently, Move to Folder, Put Flag, Mark as Expire, and Move to Deleted item folder.
  • Maintains Meta Properties, accuracy, reliability of data and attributes during removing the duplicates from Outlook PST, OST and BAK files.
  • Batch Data De-duplication feature eliminates the duplicates from multiple MS Outlook PST files at once.
  • Allows saving data in new PST File at desired location after removing duplicates from your selected PST files.


The above article discusses the need for removing Outlook duplicate emails and how to remove duplicate Outlook emails. Here, we discussed various causes of duplicate Outlook emails and the effective solutions to remove duplicate Outlook emails. We also suggested using professional Regain Outlook Duplicate Remover software that offers an easy elimination of duplicate items across and within the Outlook folder. The available free demo version of the tool will let you check its capabilities before you decide to purchase the full licensed version.