Remove Duplicate Emails in Outlook and Free Up Space

Summary: Almost every Outlook user has encountered the duplicate mailbox items issue. They want an easy and reliable solution to remove duplicate emails in Outlook. If you are also looking for the same, your search ends here. Because in this article, we will explain some simple methods to eliminate all duplicates from your mailbox. Furthermore, we will also describe the main reasons for duplicates in Outlook mailboxes. So, read the article till the end.

Basic Introduction

MS Outlook is the best-known email client for managing multiple email accounts. It provides you with various advanced features that increase your productivity. One common issue for many Outlook users is the occurrence of duplicate emails in Outlook. Like any other Outlook issue, this problem also arises due to incorrect configuration settings. So, if you want to delete duplicate emails in Outlook from your mailbox, you need to adjust these settings.

But which configuration setting do you need to modify? We will discuss the same but first, let us check why it is mandatory to delete these duplicates from your Outlook mailbox.

Why Does it Become Necessary to Remove Duplicate Emails in Outlook?

Outlook duplicate emails cause trouble to Outlook users. Therefore, it becomes necessary to delete these similar items for better performance. Some significant adverse impacts of identical Outlook mailbox items are mentioned below.

  • Duplicate mailbox items occupy additional space in the Outlook application. Moreover, too many duplicate emails may lead to a decline in the performance of the email client.
  • Another major drawback of identical emails is that it unnecessarily increases the size of the Outlook data file. Moreover, a large-sized Outlook data file leads to multiple Outlook issues.
  • Similar Outlook emails sometimes confuse the user. They cannot identify the exact time and sender of the email. Thus, it reduces efficiency and degrades the user experience.

Now, we explained how duplicate emails cause trouble to Outlook users. It is time to learn the main reasons for the creation of duplicate emails.

What Does Lead to Duplicate Emails in your Outlook Mailbox?

To remove duplicate emails in Outlook, you first need to understand the cause of the duplicate emails. Numerous reasons are there that lead to the creation of duplicate emails in your Outlook application. Some are most significant and frequent, while the others are trivial. Below we discuss a few of the prominent causes of duplicate emails.

  • Misconfigured Outlook Rules – Outlook rules are the automatic actions that Outlook performs automatically every time it sends or receives an email. When these rules are not specified correctly, they cause the creation of duplicate emails in Outlook.
  • Repeated Synchronization – When the same email account is added on multiple devices, it leads to the repeated synchronization of your mailbox data. Therefore, you will have duplicate emails in your Outlook mailbox.
  • Improper Outlook Settings – If your Outlook profile has improper settings, many identical mailbox data will get created automatically. Also, duplicate emails occurs when the Exchange server settings are not adjusted to suitable options.
  • Third-party Add-ins – Another common reason for duplicate email creation is Outlook add-ins. They are designed to add additional functionalities to the Outlook application. But sometimes, they hinder the regular operations of the tool and result in duplicate emails.

Above all reasons are responsible for duplicate emails in your Outlook mailbox. If you regulate Outlook settings to a suitable value, it will stop creating multiple similar emails in Outlook.

Now, let us explore how to remove duplicate emails in Outlook.

How to Remove Duplicate Emails in Outlook?

Depending on the reasons for duplicate item creation, you can remove duplicate email addresses in Outlook and prevent their formation by different methods. All these manual techniques are simple and effective such that any new user can perform them in Outlook. Below we provide you with the most suitable techniques to delete duplicate Outlook emails.

#1. Configure Outlook Rules Properly

As we mentioned above, improper Outlook rules create conflict between various Outlook mailbox items and lead to duplicate Outlook emails. Thus, the first thing you can do to remove duplicate emails in Outlook is to configure Outlook rules properly. It enables Outlook to not create extra copies of emails while sending and receiving mailbox data.

#2. Enable the “Do not Import Duplicate Items” Option

Whenever you import an Outlook mailbox from a PST file, there is an option ‘Do not import duplicate items.’ This feature ensures that duplicate emails will not get migrated during the mailbox import. To use this feature, follow the below steps.

  • Open the MS Outlook application in your system.
  • Click on the File button at the top menu bar.
  • After that, select the Open & Export tab and choose the Import/Export icon.
  • Now, select the Import from another program or file option and press the Next button.
  • Choose the Outlook Data File (.pst) option and hit the Next
  • Next, click the Browse button and choose the desired PST file you want to import data from.
  • After that, tick the Do not import duplicate items option and press the Next button.
  • Now, define the destination Outlook mailbox folder and hit the Finish button.

The above procedure will resolve your Outlook duplicate email issue.

#3. Adjust the Send/Receive Time

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  • In the Outlook application, click on the Send/Receive
  • After that, expand the Send/Receive Group option.
  • Choose the Define Send/Receive Groups option from the list.
  • Make sure the Schedule an automatic send/receive option is enabled and define the appropriate time duration.
  • After making suitable changes, click on the Close button.

These are some simple and effective solutions to remove duplicate emails in Outlook. After performing these steps, you can eliminate all duplicate mailbox items from your mailbox. Despite being effective, these manual methods do not guarantee your Outlook mailbox will become free from all duplicate items. So, we suggest a more advanced and reliable solution to delete all duplicate emails.

Professional Solution to Remove Outlook Duplicate Emails

DRS Outlook Duplicates Remover Tool is the best Outlook duplicate items remover to remove duplicate recipients from Outlook emails, contacts, calendars, and tasks. The application provides numerous parameters to identify duplicate emails and eliminate them from your mailbox. This software is faster and easier to use than the manual approach. You can remove all duplicate emails in a few simple steps. Moreover, the application has quite an interactive GUI, so any new user can easily use this application.

Conclusion

After reading this article, you have learned some simple solutions to remove duplicate emails in Outlook. Also, we explained the main reasons behind the creation of these emails and why it is so important to delete them. The manual methods may be tedious for some users. Therefore, we also mentioned professional software to delete duplicate emails. It is a fast, effective, and reliable approach to deleting undesired duplicate emails.

Frequently Asked Questions

Q.1 Why am I getting duplicate emails in Outlook?

Ans: Duplicate emails can appear due to various reasons such as incorrect account settings, synchronization errors, importing PST files multiple times, corrupted Outlook profile, or server issues.

Q.2  Is there an automatic way to remove duplicate emails in Outlook?

Ans: Yes, the DRS Outlook Duplicates Remover Tool is an automated way to remove duplicate emails in Outlook. It supports batch processing with several advanced features.

Q.3 Will deleting duplicate emails affect my Outlook mailbox data?

Ans: No. With the reliable method like DRS Outlook Duplicates Remover Tool, nothing affects your mailbox data. It offers a guarantee of 100% accurate result.

Q.4 Do these tools support all versions of Outlook?

Ans: Most reliable duplicate email removal tools, like DRS Outlook Duplicates Remover Tool support a wide range of Outlook versions, including Outlook 2010, 2013, 2016, 2019, and Microsoft 365.

About The Author:

I, Aaradhya Jain, a technical content writer at DRS Solutions, specializes in delivering clear, practical guides on data management, migration, and recovery tools. With a detail-oriented and user-first approach mindset, I transform complex processes into actionable insights for IT professionals and decision-makers.

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