Email duplicated on outlook 2016

Hi All Expert,

Good Day

I have a user which he has many duplicated email on different email on all the pst he has, and the clean folder command does not work.

*Windows 10

*Outlook 2016 365

Appreciate if any expert here can assist on.

Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Bernard S.CTOCommented:
You have 2 problems here:
1 - why is your user having these duplicates and how to stop new duplicates
2 - clean the dupicates
If you don't solve item 1 first, there are chances that the user will come back to you often to get helped on item 2

You don't give many details, so I'm making some blind shots
- did s/he made automatic replication or move to folders in the same pst? in differents pst?
- which pst has s/he created?
- which rules are applied to move mails to folders? psts?
Alexei KuznetsovMicrosoft Outlook MVPCommented:
You can use the free Remove Duplicate Messages utility to eliminate all email duplicates. There are also free tools for removing duplicate contacts, calendar items, etc... I recommend these tools because I'm one of the developers, so feel free to ask any further questions.
Jerry FreyIT Commented:
There could be multiple reasons for duplicate emails in Outlook 2016. Please check this blog: 

However, you can remove duplicates from Outlook using Stellar Outlook Duplicate Remover. You can use demo version of software for the verification.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Ultimate Tool Kit for Technology Solution Provider

Broken down into practical pointers and step-by-step instructions, the IT Service Excellence Tool Kit delivers expert advice for technology solution providers. Get your free copy now.

xchiazyxAuthor Commented:
Hi All,

Thank you for reverting back.

I have tried repair the pst, the cleanup feature on the home tab and none work, our side here cannot install 3rd party software without HOD approval though.

Bernard S.CTOCommented:
- did s/he made automatic replication or move to folders in the same pst? in differents pst?
- which pst has s/he created?
- which rules are applied to move mails to folders? psts?
Bernard S.CTOCommented:
Proposed solutions will be useful for other askers.

Asker did not provide answers that might have been useful for the case
Jon MaximCommented:
Checkout this blog post to remove duplicate emails from outlook. Read and do it yourself.

It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.