How to Remove Duplicates in Outlook – Know How


Are you looking for a solution to remove duplicates in Outlook? If yes, then your research ends here. This article will show you an easy way to delete duplicate Outlook emails. So continue reading this article.

Email is very important in any organization because most of the communication will happen through them. When it comes to email clients, Microsoft Outlook is the first choice. Basically, Outlook has many powerful features to manage your emails efficiently. However, like any mailbox, Outlook users face recurring email problems.

The number of emails in our inbox grows every day. Also, when duplication occurs, managing email messages becomes a difficult task. It also affects the user’s work in many ways. For example, storage problems, slow performance of Outlook, etc. Therefore, it is very important to deal with duplicate emails, so in the next section we will talk about how to remove duplicate emails from Outlook.

 What are Duplicate Files?

The printed products can be anything, such as email messages, notes, calendars, contacts, tasks, or attachments, and can share the same storage space. email files stored in Outlook inbox or archive folders are called duplicate files. Some emails are for announcements, newsletters, announcements or announcements for new projects, etc. are still being prepared.

Reasons for Remove Duplicates in Outlook

There are several reasons why Outlook creates a duplicate in your mailbox. Some of the reasons why Outlook creates duplicate emails are:

  • Different companies send the same email to get users’ attention. This leads to duplicate emails.
  • With the phone, laptop, etc. due to incorrect synchronization, the same messages or contacts are copied in different folders
  • Invalid code in the purchase mode of Microsoft Outlook creates duplicate emails in your mailbox.
  • Incorrect linking of different files can cause compatibility issues in Outlook.
  • Scanning files sent by email from some antivirus software can create duplicate emails in Outlook.

Prevent Outlook from Sending Duplicate Emails

Sometimes antivirus software can duplicate emails. Sometimes it is a combination of Outlook and antivirus. Antivirus application scans out emails as soon as they are sent. So it was sent twice because of some mistake. So, disabling scanning of incoming mail will solve the problem.

  • Restrict Outlook from Creating Contacts

Microsoft Outlook Stores email and fax numbers as two download. So, instead of manually entering the people, saving the people in an Excel sheet that has email and fax numbers and then importing them will solve the problem of duplicate calls.

  • Prevent Outlook from Creating Competing Appointments

The purchasing process can be limited if you stop Outlook from running on another Microsoft Outlook to create recurring appointments. Running two Outlooks at the same time can result in duplicate conversations.

How to Remove Duplicates in Outlook?

  1. use account settings
  2. From import and export functions
  3. Change settings to remove Outlook PST duplicates.
  4. With the built-in Outlook cleaner.
  5. With Outlook Duplicate Remover Utility.

Remove Duplicate Emails from Outlook Using Account Settings

  • Start shopping mode on Microsoft Outlook to the menu
  • Select information
  • Select Account Settings
  • Find the name of the account you have set up
  • If the same account is set up more than once, cancel the refund
  • To delete, select the email account and click delete
  • When you have removed the duplicate account, click Close

Remove Duplicate Emails from Outlook Using Import and Export

Follow these steps to delete duplicate emails in Outlook:

  • Open Microsoft Outlook in the shopping cart.
  • Click on the menu item
  • Select Open and then Export
  • Now select import/export
  • Select to import from another file or program
  • Click Next
  • Select the Outlook file, and select Next
  • Now find the PST file from the file path and enable “Do not import duplicates” and click Next
  • Select the Outlook file, send all the files, and after selecting the folder, select the folder
  • Now click Done to continue

Use the built-in Outlook Cleaner to Remove Duplicates Messages in Microsoft Outlook

  • Outlook Cleaner Tool is a tool built into the Microsoft Outlook Store. This allows users to delete duplicates in Outlook:
  • Start shopping mode on Microsoft Outlook
  • Select the clean option to expand all the options
  • This will display three options: Delete Session, Delete Folders and Subfolders, and Delete Folder
  • Now click on Delete folders and subfolders
  • select yes and continue
  • Click on the location and the Outlook window will appear
  • Click the Browse button to specify the location of the PST file
  • Select Folder will appear, then click Deleted Items
  • Now select OK

Disadvantages of the Manual Method

All of the above solutions are only applicable if you have a small PST file containing only a few hundred emails. However, if you have a lot of email in Outlook, you may encounter the following limitations when using it manually.

The number of duplicates in the Outlook mailbox cannot be determined. Therefore, there is no solution to find and remove duplicate emails from Outlook.

The cleanup tool produces an error message such as “No words were cleaned. Only words that match the cleanup fields are discarded.” during the deduplication process.

Automatic Solution to Duplicate Items in Outlook Account

The above process to remove duplicate messages from Outlook is labor intensive and time consuming. So, with the help of SysTools Outlook Duplicate Remover Software, we can quickly and easily delete emails from Outlook. This is the best way to delete duplicate emails from the Outlook PST file. This application is completely safe to use and can delete copies of all Outlook files and folders without data loss. This application is designed with every user’s needs in mind. You can find and remove duplicate emails in Outlook by comparing certain attributes. For example: Subject, Recipient, Cc, Sender, etc. Also, users can remove duplicates of multiple PST files by adding the option. It can be considered as a solution to meet all the needs of users. In addition, this tool also allows you to remove attachments from Outlook messages.

Steps to Remove Duplicates in Outlook 2021, 2019, 2016, 2013, 2010

  • Download and Run the Utility on your any Windows Machine

download Outlook duplicates Remover

  • Upload the Outlook data PST file by clicking “Add File/ Folder”

Add Outlook files

  • There are two ways to remove duplicates: in a folder or between folders

Select Folders

  • Click the Change button to select a location to save the created PST file

Click on Change button

  • Select files such as email, contacts, calendar, contacts, tasks, and notes to remove duplicates

Select data items

  • Now Select Specify Duplicate Criteria to specify the attribute or field to remove duplicates

Select Specify Duplicate Criteria

  • You now have the option to apply filter options, giving you the freedom to add as many date filters as you like

apply filter options

  • Choose an action to apply to duplicate items, such as Permanently Delete, Move to Deleted Folder, Move to Folder, Put Flag, and Mark Expired

apply to duplicate options

  • After completing all the process, Hit the “Next” button to start the deduplication process

deduplication process is complete

  • The following message will appear upon completion. You have completed the process of deleting duplicate emails from Outlook. Click on the OK .

completed the process of deleting duplicate emails from Outlook

Key Features of this Application

  • Delete duplicate Outlook emails, calendars, contacts, tasks, journals, notes and more.
  • It helps to delete duplicates items data in Outlook folders.
  • Delete duplicate emails from multiple files at once in batch mode.
  • This PST deduplication tool does not increase PST file size.
  • To use the tool, it is necessary to use the MS Outlook e-mail client in working mode.
  • Extracts duplicate Outlook items across multiple dates
  • Eliminate duplicate data Outlook items from ANSI and UNICODE PST of any size
  • All versions of MS Outlook email client and Windows operating system are supported.


Handling duplicates is a difficult task that users face. There are many ways to make this task easier for users to remove duplicates in Outlook 2021, 2019, 2016, 2013 and 2010 as discussed above. This blog includes all manuals and solutions for users. Users can choose among these according to their needs.

Read More: Import EML Messages to Thunderbird


Please enter your comment!
Please enter your name here