Solution: To remove duplicate emails in Outlook, sort emails by subject, sent, or received date, and manually delete rest of them. Use Outlook’s Clean Up tool to only remove redundant messages within single conversation or subfolders. To deduplicate large PST or OST files, re-import files by enabling Do Not Import Duplicates feature or try dedicated removal software by SysTools to deduplicate emails within or across folders.
We know that there is an increase in number of emails in our mailboxes, which makes our mailboxes cluttered. However, duplicate emails are one of most common reasons when Outlook starts to slow down. It becomes important to reclaim our storage space by getting rid of duplicate emails in Outlook mailbox. As a result, it enhances overall performance of Outlook.
Moreover, these redundant messages can occur due to many reasons, such as synchronization errors, incorrectly applied rules, importing same data file multiple times, and many more. So, in this article, we will discuss each effective way to delete duplicate emails in Outlook to speed up Outlook performance.
How to Remove Duplicate Emails in Outlook – Fastest Way
Follow these steps:
- Firstly, download & run SysTools Outlook Duplicate Remover Tool.
- Add supported files to upload on Add file option.
- You can change Destination if you want to keep your output at a different place.
- Apply filters to make it more accessible to detect duplicates.
- Click OK when the process is done.
Why Do Duplicate Emails Appear in Outlook?
Now, before going towards the solution part, let’s find out why duplicate emails are appearing in Outlook and how it can be important to remove duplicate emails Outlook. So, have a look at the reasons behind this.
- Sync Issues between Devices or Accounts: If you have configured the same email account multiple times, then the incoming data will get synchronized again and again. This is also common with multiple IMAP or Exchange accounts, which can result in duplicates, and users end up remove duplicate emails in Outlook mailbox.
- Improper Mailbox Setup: It is also possible that you have incorrectly set your mailbox while creating an account. Therefore, you might be receiving duplicate emails in Outlook as well as calendar, contacts, and notes again and again.
- Incorrect email settings or filters: When rules are misconfigured, they can send the same message to multiple folders or send the same message again based on the rule configuration settings. This usually happens where rules are overlapping or indefinitely looping while handling messages.
- Accidentally importing the same PST files more than once: You can create duplicates of all the emails because you imported the same PST file more than once without excluding the duplicates. This usually occurs when the user forgets to click the exclude duplicates option.
- Antivirus or add-ins conflicting in Outlook: Part of the issues can be with certain antivirus or Outlook add-ins that can scan incoming messages and re-deliver at some point, causing duplicates. They can also conflict with the way Outlook fetches emails to store in a mailbox, especially when the bypass real-time scanning feature is off.
All such reasons make users think twice about how to get rid of duplicate emails in Outlook. Thus, to make this task easier, there are multiple ways on how to delete duplicate emails in Outlook.
Watch a Quick Tutorial on Remove Duplicate Emails Outlook
4 Proven Methods to Remove Duplicate Emails in Outlook?
There are multiple ways to delete duplicate emails in Outlook. You can choose between them as per your requirements if you aim is comprehensive mailbox management you may need to find the ways to extract email addresses from Outlook for separate record keeping. The following methods are mentioned below:
- Import/Export Option to Delete Duplicate Emails
- Use Outlook’s Clean Up Tool
- Deduplicate Outlook Emails in Preview Mode
- Using Expert Certified Software by SysTools
Let’s learn and understand them one by one:
Important: Make sure to take backup of your Outlook mailbox before performing any of these methods. This way if something goes wrong, you will have the original mailbox file.
#Method 1: Import/Export Option to Delete Duplicate Emails
With help of Import/Export feature, you can also remove duplicate email messages in Outlook. This method allows you to remove duplicate items in Outlook by exporting your mailbox without duplicates and then re-importing it. Follow steps mentioned below in two stages:
Stage 1: Export without duplicates
- Open Outlook.
- Now, go to File, then Open & Export, then Import/Export.
- Here, select “Export to a File” and then choose Outlook data file (PST).
- Select all folders that you want to deduplicate.
- Finally, choose “Do Not Import Duplicate Items” and finish procedure.
Stage 2: Import without duplicates
- Open Microsoft Outlook and navigate to File → Open & Export → Import/Export option.
- In Import and Export Wizard window, choose Import from another program or file option and click on Next button.
- Now, choose Outlook Data File (.pst) on Import a file window and click on Next button.
- On Import Outlook Data File window, simply Browse .pst file and check Do not import duplicates option → Next button.
- Now, choose Outlook Data File and select “Import to same folder in“. At last, select mailbox from which emails were exported in Stage 1 and click Done.
#Method 2: Use Clean Up Tool to Remove Duplicate Emails from Outlook
Microsoft Outlook has a Clean Up Tool that lets you delete duplicate items from Outlook. This built-in solution can serve as a basic removal feature by Outlook for cleaning up within a single conversation or folder. To use it properly, follow steps mentioned below:
- First of all, open MS Outlook application
- Then, click on Clean Up option from ribbon bar and expand all options.
- As you expand it, three options will be displayed, i.e., Clean Up Conversation, Clean Up Folders, and Clean Up Folders & Subfolders.
- Here, you have to choose Clean Up Folders & Subfolders option
- Now, a Clean Up Folder dialog box will pop up, asking you whether to proceed with clean up or cancel. Simply, click on Clean Up Folder option
- After that, click on Settings option to enter Deleted Items folder location manually
- As you click on Settings, an Outlook Options window will open. Click on Browse button to add PST file
- Now, Select Folder pop-up will appear in front of you. Choose Deleted Items → OK button
- Finally, click on Clean Up Folder option to remove duplicate messages in Outlook mailbox.
#Method 3: Deduplicate Outlook Emails in Preview Mode
This method relies on visually checking and comparing emails and then deciding on deletions. It works most efficiently when there are only a few duplicates in a known folder.
Steps to Use Preview Method for Removing Duplicates in Outlook:
- Switch to Preview Mode
- Change view of PST folder containing duplicate emails to “Preview” mode in Outlook.
- Change view of PST folder containing duplicate emails to “Preview” mode in Outlook.
- Differentiate Columns for a More Favourable Comparison
- Access to View Settings menu.
- Click on Columns… button.
- Choose from available columns for display by clicking Add (e.g. Size, Subject, Date, Sender).
- Sort your Emails for Easily detection of Duplicates
- Click Column Header (for example, “Size”) to group emails according to shared characteristics.
- Otherwise, use Sort button in View Settings and sort your emails based on filters like Subject, Received Date, Sender, etc.
- Go to View > View Settings > Sort…
- In Sort window, from drop-down lists, select your sorting criterion and click OK.
- Click OK again in Advanced View Settings dialog box to save changes.
- Go to View > View Settings > Sort…
- Manually Sort and Delete Duplicate Emails
- Once all emails are organized, you can start a visual comparison to determine which ones would be counted as duplicates.
- Now, Outlook remove duplicate emails manually.
Tip: Users can also try View > View Settings > Filter and set criteria for different Subject and Body. This will help you to save your time and effort in identifying and deleting duplicates manually from entire mailbox.
This method takes considerable labour, especially when there are a lot of emails organized into several folders. It would also require much effort to review the messages to make sure one does not delete that all-important email wrongly.
However, if it is only a few duplicates and they are all at one particular known location, this should work quite well for you. But perhaps for larger-scale removal of duplicate files, you might consider automated applications or other filtering methods as being more efficient.
Limitations of Manual Duplicate Email Removal in Outlook
All above-discussed manual solutions are useful only when there is a small-sized PST file containing only hundreds of emails. But if you have a large number of emails in Outlook, you might face the following limitations while using the manuals.
- Unable to detect exact number of duplicates in Outlook mailbox. So, to locate and remove duplicate emails from Outlook through manual solution will not be reliable option.
- This clean-up tool starts generating error messages like “No messages were cleaned up”. Only messages that satisfy your cleanup settings will get moved to trash folder while deduplication process.
How to Delete Duplicate Emails in Outlook Professionally?
If a user is looking for a simple solution or wants to avoid the manual solution, go for a professional alternative automated solution which is developed by SysTools. This professional software which can help you to remove duplicate emails in Outlook effectively.
The software is designed to keep all the requirements of users in mind. One can detect and remove email duplicates Outlook by matching particular attributes. For example, subject, to, cc, from, etc. In addition, a user can also delete duplicates from multiple PST files in bulk via Add Folder option. It can be treated as a one-stop solution to fulfil all the basic requirements of users. Along with this, the utility also offers the facility to remove duplicate attachments from Outlook.
Working of This Trusted Tool
- Download and install the duplicate email removing utility.
- Click Add File or Folder button to upload supported files.
- You can choose between the two options to delete duplicates: Within or Across Folders.
- Choose location to save the resultant PST file.
- Choose data items, i.e., Emails, Contacts, Calendars, Journals, Tasks, and Notes, to remove duplicates.
- Now, choose Specify Duplicate Criteria option to specify to remove duplicate emails in Outlook.
- After that, select removal action as “Delete permanently” or “Keep one copy with you“.
- Click Next as you are done with the process of removing duplicate emails from Outlook
Also Read: How to Remove Duplicate Contacts in Outlook?
Prevention Tips for Duplicates in Outlook Mailbox
After cleaning your mailbox, users should remember pointers listed below to avoid redundancy problems in future.
- Always check while importing PST file that “Do Not Import Duplicates” option is enabled.
- Try not to configure same Outlook account more than once, as it can prevent syncing errors.
- Adjust your Send/Receive frequency to prevent messages from same sender, subject, etc., on your account.
How to Remove Duplicate Emails in Outlook for Mac?
To delete duplicate emails from Outlook on Mac, one can use either manual method, which is Clean Up built in tool, or manually delete duplicates. However, they are prone to error, which can result in data loss and is very time taking process. Also, it is only if users want to deduplicate small number of emails.
In such case, we recommend using an automated desktop based program, which is SysTools Mac Outlook Duplicate Remover Tool. This professional utility allows users to scan and remove duplicate emails Outlook Mac version without any data loss, along with its integrity. It is compatible with various editions of Mac operating system. One can download and try its free demo version to delete duplicate emails in Outlook.
Comparison of Outlook Remove Duplicate Emails Options
Since the Preview method is all about how users find and Outlook delete duplicate emails process by the user, we are not going to include it in the comparison table.
|
Features |
Import/Export Option |
Outlook’s Clean Up Tool |
Professional Software by SysTools |
|
Processing Speed |
Moderate |
Fast |
Very Fast |
|
Easy to Use |
Moderate |
Easy |
Very Easy |
|
Accuracy |
Only Exact Duplicates |
Consider Message Header |
High |
|
Bulk Removal |
No |
No |
Yes |
|
Advanced Filters |
Limited |
Limited |
Yes |
|
Data Security |
Moderate Risk |
Low Risk |
No Risk |
|
Special Features |
Basic Detection |
Built-in Feature |
Specific Duplicate Criteria |
|
Multiple Folder Support |
Single Folder |
Yes |
Yes |
|
Best For |
Small Mailboxes |
Moderate Sized Files |
Large Mailboxes, Multiple Data Files |
Concluding Words
In this article, we got to know that duplicate emails are most common problem faced by users, but this task becomes easier once you know which solution to use. Thus, this well explained guide has covered all possible manual and professional ways on how to remove duplicate emails in Outlook. Users are suggested to opt for best and automated software, which will help them save their time, effort, as well as their important data. To avoid risk of deletion, always take a backup of your data files. If you are still facing any queries, then you can contact our support team for quick solution.
FAQs on How to Delete Duplicate Emails in Outlook?
Q.1 Can Outlook Remove Duplicate Emails Automatically?
A. It can only delete to some limited extent. As Outlook cleanup feature only removes redundant emails within a single conversation, or Import or Export feature only helps when you import your data file again. Thus, for an automatic solution, you are required to use professional tool.
Q.2 Why Do I Keep Getting Duplicate Emails in Outlook?
A. This may happen due to wrongly configured email rules, importing PST files more than once, syncing errors across IMAP or Exchange accounts, or using third party antivirus applications, which delay in receiving emails in Outlook.
Q.3 What Should I Do If I Accidentally Delete Non-Duplicate Emails?
A. Go to the deleted item folder, where you may find the deleted emails from Outlook, or you should go for the suggested software above for better results.
Q.4 How Can I Remove Duplicate Emails in Outlook Without Losing Important Messages?
A. You can remove duplicate messages in Outlook by first backing up your Outlook mailbox, then using the cleanup feature or using an advanced program designed by SysTools to remove email duplicates Outlook.