Emails play a vital role in running an effective business, as it is a basic mode for sharing data information. Almost all the business users use MS Outlook as its email application for proper management of emails. From the business viewpoint, they have about hundreds of communications on their mailbox of Outlook. Due to which, at the time of working they face an issue of duplicate emails in the mailbox as several of emails are stuck in many folders.  If there are some duplicate emails in mailbox then, users will face few issues while working over Outlook like the decrease in performance of MS Outlook, the corsage of storage limitation of Outlook, etc. In the following write-up, we will discuss the causes behind it and how to remove duplicate emails from Outlook PST file.

Causes for Behind Duplicate Items
There are various reasons because of which, duplicate emails may occur in MS Outlook. Some of them are mentioned below:
1. Getting various copies of exact mail is due to a reason as various companies send the same emails, blogs, newsletters, etc. back to back for gaining the user’s attention.
2. When synchronization process continues through laptop or mobile device, then many times the process get finished, which results in duplication.
3. Many times, an option of Messages Leaving is active, which results in undesirable duplicate messages on the mailbox.
4. Merging of numerous files imperfectly results in duplication.

Techniques for Removing Duplicates Mail 
Before learning or understanding about how to remove duplicate Outlook items, it is important to firstly understand a way to how to get free from such problem. Always preserve the step and implementation of MS Outlook by cleaning the whole mailbox in daily. By cleaning, it does mean to eliminate the mailbox data, but to remove the unwanted items. In this way, users can keep their Outlook up-to-date. There are some ways mentioned below that helps in removing the email duplication from MS Outlook.

Check Settings of Account 
Most of the time, users can attempt in configuring Microsoft Outlook files more than a time, which adds various accounts to Outlook while synchronizing the PST files, which made a copy in Outlook. It can be removed by following few steps:
1. Open MS Outlook on your system.
2. Go to file option, select Info >> click on Account Settings.
3. In the Windows of account settings, there is a mail tab. Search out configured account name. 
4. If the account is configured with the similar name more than one time then, remove extra account by selecting mail account >> choose to Remove option.
5.  Click on the close button to the duplicate account is removed. 

Import and Export Option
There are various steps that are mentioned, which helps users in removing email duplicate from Outlook.
1. Firstly, start MS Outlook on your machine.
2. Select file Option >> choose Open >> Export option.
3. Now, click on the option of Import/Export.
4. Choose an option of import from other file or program and click next.
5. Select PST file and click next.
6. Browse data file to import and check an option of “do not import duplicates”. Then, choose next.
7. Select Outlook data files to export the complete data and select exact folder after clicking on the particular folder and click Finish.
8. Change the view settings for eliminating duplication.

For another version of Outlook (2002, 2003. 2007)
1. In Outlook 2002 and 2007, choose an option of the current view, which is under view menu for moving an option from folder to table view.
2. In Outlook 2003, select current view for changing the option from folder to table view, which is under arrange by an option on the view menu.
3. Click on the header of the column and choose an option of field chooser.
4. Click on all name fields items from displayed list.
5. Drop the changed field to the heading of the table.
6. Duplicate item will have diverse date from initial date set. Click on Altered headings then, it will be simple to understand.
7. Select an item from list set, which is needed to be deleted and press Shift+ delete key for permanent deletion.

For Outlook 2010
1. Select change view option from view and select option of preview for changing the folder to table view option.
2. Choose an option of field chooser from a column of the header.
3. Select all email fields to option from the field chooser.
4. By selecting the changed heading, check the duplicate item, which is variant from initial item set.
5. Choose the first and last item, which is needed to be deleted.
6. Press shift + delete and eliminate duplication by permanently data items deleting.

Clean up Tool of Outlook
It is an inbuilt utility of MS Outlook, which permits users for removing duplicates from Outlook files as well as folders by following given steps:
1. Open MS Outlook on your machine.
2. Select cleanup option for expanding all options.
3. Once it is expanded, then three options will appear, i.e. clean up folders, clean up the conversation, clean up folders & subfolder.
4. Now choose an option of clean up folder and subfolders.
5. Click yes to continue.
6. Another option, which is showing is settings and choose settings option to manually provide the location of deleted folder items.
7. After selecting the settings options then, MS Outlook option Window will be displayed.
8. Click on browse option for providing the location of Outlook PST file.
9. Choose the folder that will pop-up and select an option of deleted items >> click Ok.

Expertise Solution
There is a software namely Outlook Duplicates Remover. It is a straight way for removing duplication from MS Outlook items. The software is completely safe as well as secure to use and remove all the duplication from files and folders of MS Outlook without losing a data.

Conclusion
Email duplication creates a great confusion of everyone while working. Therefore, it is important to remove duplicates from PST File to gain Outlook performance back. For removing the duplicate items, manual methods and expert's solution to remove Duplicate emails from Outlook are discussed in the above discussion that makes easy for users to utilize Outlook in a better way.