How to Stop Receiving Duplicate Emails in Outlook

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Written By Ashwani Tiwari
Anuraag Singh
Approved By Anuraag Singh
Published On June 9th, 2025
Reading Time 7 Minutes Reading

There are lots of times when Outlook users also receive duplicate emails. Receiving Duplicate emails in Outlook can be quite annoying – duplicate messages can clutter our inbox, slow down our performance, and cause confusion, particularly in a work environment. Duplicate messages can impact your productivity, whether you are using Outlook 2021, 2019, 2016, or earlier versions of Outlook.

This article provides the top 5 ways to fix duplicate messages in Outlook, which includes some manual options as well as a professional option. If you are still thinking, how to stop receiving duplicate emails in Outlook, continue to read on.

What are the Causes for Outlook Receiving Duplicate Emails?

Before learning how to stop receiving duplicate emails in Outlook, it is good to know the main reasons for this. Duplicate emails in Outlook are usually related to Outlook’s settings, the Outlook data files, and any interference from external programs. Let’s talk about them briefly:

1) Incorrect Outlook Account Settings
Outlook may download the same email twice for every message if you set up the same email account multiple times.

2) Email Rules and Filters Clashing
Outlook could put the same email in more than one folder if you had applied some filters can cause overlap or conflict.

3) Antivirus or Firewall Interference
Some security software may stop the process of syncing emails, which can cause the problem of receiving duplicates emails in Outlook.

4) Outlook Synchronisation Error
If there are any problems with syncing between the mail server and the Outlook client, especially when using IMAP or Exchange accounts, which might cause Outlook receiving duplicate emails.

5) PST File Corruption
If your PST file is corrupted, Outlook may have trouble with performance and duplication of data, especially if the file is quite big.

These are the core reasons possibly causing the problem in Outlook. Let’s discover what steps or methods can resolve Outlook receiving duplicate emails.

5 Best Fixes for How to Stop Receiving Duplicate Emails in Outlook

If you’re wondering how do i stop receiving duplicate emails in Outlook, then these 5 methods include both manual and great automated tools which help to resolve the cause of Outlook. These methods are:

  1. Reconfigure or Remove Duplicate Accounts
  2. Review and Edit Outlook Rules
  3. Temporarily Disable Antivirus Email Scanning
  4. Repair Outlook Data Files (.PST)
  5. Excellent Automated Removal Tool

Let’s talk about them in brief:

Method 1: Reconfigure or Remove Duplicate Accounts

Outlook may treat the same account as two different ones with different inboxes if you set it up more than once. It will then download the same emails over and over again.

Pros:

  • It’s quick and easy.
  • Stops the same account from sending duplicate emails in the future.
Cons:

  • You might lose some options that are unique to your account.
  • Doesn’t get rid of copy emails that are already there.

Method 2: Review and Edit Outlook Rules

If the rules are not set up properly or overlap, the same message can be moved or copied more than once.

Pros:

  • It makes it easier to find emails.
  • Deletes rules that were sending duplicate emails.
Cons:

  • It takes a long time to find bad rules.
  • Doesn’t fix emails that have already been sent twice.

Method 3: Temporarily Disable Antivirus Email Scanning

Antivirus software has email scanning features which could re-fetch messages, resulting in duplicates.

Pros:

  • Easy to do.
  • Good way to confirm that security software is the culprit.
Cons:

  • Temporary reduction in email security while you perform the test.
  • This is not a permanent fix – either way, you will need to force email scanning to be reconfigured or use exemption rules.

Method 4: Repair Outlook Data Files (.PST)

A PST file that is damaged may cause Outlook to not work correctly, including re-sending or re-downloading emails/messages.

Pros:

  • Can often repair internal file-level issues.
  • It can also help improve Outlook performance overall.
Cons:

  • Cannot repair a severely damaged file.
  • Risk of losing data if not have a backup in the first place.

Note: If you are receiving duplicates in Outlook, then you should avoid these manual methods as they are very time-consuming, more likely to result in getting lose of data unintentionally or accidentally. So, I would recommend going for manual and steady methods, choose a better, trusted, and best automated tool which can resolve the problem in seconds.

Method 5: Automated Tool to Fix Receiving Duplicate Emails in Outlook

If you’re still searching for an answer on how to stop receiving duplicates in Outlook, the best fix is to use a professional and automated tool. SysTools Outlook Duplicate Remover identify mailboxes and deletes duplicates, including emails, notes, journal, calendar events, without any errors and risk of data deletion.

The tool works with all versions of Outlook (2021, 2019, 2016, 2013, and more) on both Windows and Mac. It has advanced filters to help remove duplicates from within folders and across folders, using specific criteria such as subject, time and sender. Along with this, the tool also offers to remove duplicate attachments from Outlook to get rid of similar emails having attachments.

Pros of the Outlook Duplicate Removing Tool

Some benefits are mentioned below:

  • Error-Free Detection of Duplicates

The tool examines your Outlook data and finds duplicates, which it identifies by multiple things (subject, sender, attachments, date), so only the duplicates are removed which helps to maintain the accuracy of data.

  • Remove Thousands with One Click

This allows you to remove duplicate items at mass level, which can be in many folders or files, with a single action, saving you a lot of manual work and time.

  • Preserves Data Structure

When deleting duplicates, it preserves your original data structure and lessens the risk of accidental deletion or data loss.

  • Unlimited Filter Options

You can even filter by date range, item type, or select folders so you can decide exactly what’s being identified and cleaned.

Working Guide of the Best Alternative Method

Steps are as follows:

  1. Download and install the SysTools Duplicate Removing Software.
  2. install

  3. Choose Add Files to add supported files.
  4. add file button

  5. Select Destination if you want to save file on different path.
  6. destination

  7. Select Specify Duplicate Criteria (Subject, To, From, Date, etc.)
  8. apply filters

  9. Click Next
  10. next

  11. Click Start to begin process of de-duplication.
  12. start

Bonus Tips to Know: How do I Stop Receiving Duplicate Emails in Outlook?

#1 Manage Your Inbox Regularly
Use the Outlook cleanup tool, which helps to remove similar emails and outdated conversations and make your mailbox productive and smoother.

#2 Check Sync Status and Server Settings
A lot of sync errors could mean issues with your server or connection settings. By keeping these settings current, you’ll minimise or even eliminate issues.

#3 Universal Messaging with IMAP
IMAP ensures that your data syncs effectively and avoids downloading similar emails again. POP downloads your emails and saves them locally, which increases the likelihood of duplicates.

Conclusion

Outlook receiving duplicate emails is a fixable situation. Whether this is due to how you set up your accounts, conflict between rules, or data corruption, the proposed approaches above offer both easy fixes and long-term solutions.

If you’re still asking, “How do I stop receiving duplicate emails in Outlook?” the most dependable and time-efficient option is the Outlook receiving duplicate emails remover Tool, which is a professional utility that provides a painless cleanup and future duplicate-removal maintenance plan.

  author

By Ashwani Tiwari

Being a Chief Technical Analyst, I am aware of the technicalities faced by the user while working with multiple technologies. So, through my blogs and articles, I love to help all the users who face various challenges while dealing with technology.