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Duplicate Email Remover

Duplicate Email Remover

Current version: 3.0

Duplicate Email Remover helps you clean up duplicate email messages and posts in Microsoft Outlook.
It is a very fast, powerful and safe tool which processes completely identical items only.

To find and delete duplicate contacts, notes, tasks, journal and calendar items, please try another software — a Duplicates Remover for Outlook.

Duplicate Email Remover enables you to:

  • Delete duplicate emails;
  • Mark duplicate messages with the flag Red flag;
  • Copy duplicates to the specified folder;
  • Move duplicates to any folder;
  • Recognize duplicates in the same folder, or in different ones;
  • Process duplicates in Public folders on the Microsoft Exchange Server.

Do your duplicate email messages have minor differences? Duplicate Email Remover will help you to process these items too! You can select the fields on basis of which the program will compare items and then will detect duplicates.


Frequently Asked Questions about duplicate messages deletion add-in for Outlook

Question: I have around 500 duplicate emails in Outlook. I selected the default settings for everything and it says it scanned all ~12000 emails but found no mail duplicates.

Answer: You can see 8 search criteria in the step 4 of 4 of the ‘Duplicate Email Remover’ wizard - and 3 criteria are critical: "Text", "Subject" and "Sender E-Mail" are the basic fields in the process of recognizing duplicated messages in Outlook folders. If messages have different values in any of these fields -- they are not duplicates, according to common sense. Other, uncritical 5 criteria are active by default – but you can remove the checkmarks from these fields to relax the search process (one by one, in turn). In the most of cases, Internet Headers are different in messages even if they look like exact copies.

Question: I have run the Outlook duplicate email remover various times using various features and criteria. I have even run it on an individual folder and I can still see some duplicate emails despite it telling me there are no email duplicates in Outlook folder.

Answer: If the programme finds no more duplicates, in all probability no more exact copies exist. If reducing all 5 uncritical search criteria in the step 4 of 4 does not help - check your messages: an issue is known with some antivirus tools which add a unique stamp into the Outlook message body, and messages with differences in message text are considered to be non-duplicates in such a case.

Question: Your duplicates remover for Outlook works very well and I just have one issue: it is picking the wrong duplicate of 2 items – the more recent one. Is there a way we can get the add-in to pick up the older record?

Answer: Duplicate Email Remover analyzes the size and the date of Outlook items before processing - and it usually considers the larger email message is the "original" - and keeps it, and all smaller items are being processed as duplicates in such a case. Usually, the more fields contain data, the larger is the size of the item. If all the fields are similar (i.e. have the same size) – the duplicated mails remover add-in will consider the oldest item is the "original".

Question: I have two identical e-mail messages in an Outlook folder with one small but important difference between them: One has been replied to, so its "Icon" has an envelope with a purple "back" arrow. Of the two "duplicates," I strongly prefer to keep the one that was replied to-- however, your email duplicates remover saw it as the duplicate to be deleted. Can the add-in be made to keep "replied to" or "forwarded" messages over messages with no such action?

Answer: It looks like in your mailbox, unreplied message copies are older (or/and probably larger). But Duplicate Email Remover gives you a possibility to perform a search for duplicate items across the Outlook folders, and with the system of priorities. So, you can configure a regular Search Folder in Outlook, filter your messages by “Tracking Status”, move replied and unreplied messages to different folders, and then run Duplicate Email Remover over a group of your folders: you will be offered to set the prior folder in the 2nd step - and messages in it will be kept as originals.

Question: At the end of the search, the Outlook duplicate remover states it has found hundreds of duplicates, but I can still see them in my folders.

Answer: The Outlook add-in provides you with the processing report after completing comparison. Please expand it, or export to see its full version with the reasons: in order to process Outlook duplicates, our add-in requires full access permissions to the folders. If you process shared or public folders where you have limited permissions, processing duplicates might fail due to insufficient rights. Please contact your mail server administrator for full access permissions to those Outlook folders.

Question: After opening the application, choosing the mode of search in the step 1, and selecting "next," I get a pop-up Mapi Error.

Answer: In the step 2 of the add-in wizard, your Outlook folder tree is loaded to the add-in – and if it contains folders where you have limited access, or these folders are currently unavailable, the duplicate remover displays the errors. Usually, if you ignore such an error (it may occur as many times as many unavailable folders are there in the folder tree), the rest of you folders will be finally loaded, and you will be able to process them. If your folder tree is not loaded even after ignoring errors, please contact our support staff with the information about your Outlook version and account types.

User testimonials
I decided to test DER on our own systems before recommending it to clients. We had multiple Outlook email files on various machines, due to travel, migration and backups, housing nearly 1 million emails accumulated over many years. Because of the unique nature of the business, these cannot be archived but must be accessible regularly. DER allowed us to consolidate these various files, reducing the total emails which were on the system by more than 300,000, and saved us many GB of storage space since our emails frequently also contain large attachments. Not only did DER allow us to reduce the file size and bring order to the disparate email boxes, it further helped us streamline our operations, and save invaluable processing time. We figured that it would have taken literally MONTHS of focused and dedicated work to even attempt to clear out the duplicates and bring a higher-level order to our system. DER did this and more within a handful of hours, while we concentrated on providing services to the customers of the business instead. We now look forward to using the attachment processing tool to reduce the file size and thus processing time even further. I will absolutely recommend this to our clients who are using Outlook. Thank you for such a superior product!

Michael Hemmelgarn
MHA Consulting

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