Eliminate Duplicates from your Thunderbird Mailbox


As of right now, Thunderbird is an open-source, dependable, and cost-free email client offered by the Mozilla Foundation. Integrating several webmail accounts is a popular option among users. It occasionally creates copies of redundant emails, which expands the size of the inbox and uses a lot of storage space. It’s advised to eliminate duplicates from your Thunderbird mailbox in order to solve any issues that may have arisen from them. This post will walk you through a simple method for getting rid of duplicate emails in Thunderbird.

Need to remove Thunderbird duplicate emails

A few identical emails in Thunderbird are not a huge deal, but thousands of duplicate emails necessitate the removal of all duplicate emails using a suitable method. There are several opportunities for users to receive multiple mailboxes when they use Thunderbird’s webmail program.

Chances of Receiving Duplicate Emails

Find out further causes of duplicate emails in Thunderbird.

Problems relating to the server: Sending and receiving emails in an email client depends heavily on the server. Occasionally, the Thunderbird application experiences email duplication due to the server downloading the same email several times.

Problems on the sender’s end: Occasionally, the sender will send the same email message repeatedly, which causes Thunderbird to receive multiple emails from the recipient.

Unintentional User actions: When a user copies an email to another subfolder within Thunderbird, it results in duplicate emails being stored in Thunderbird due to the applications many directories and subfolders.

How Do I Delete Thunderbird Duplicate Email?

You have the option to manually eliminate duplicate mailboxes from Thunderbird. 

If you’re looking for a quick solution to remove of duplicate emails in Thunderbird, utilize CubexSoft expert MBOX Duplicate Remover. It will automatically load Thunderbird mailboxes and eliminate duplicate emails from every folder.

How to manually eliminate duplicate emails in Thunderbird

  • Launch the Mozilla Thunderbird software.
  • Select Add-ons from the drop-down list under the Tools menu.
  • After the Add-on Tab opens, search for “remove duplicates” and press the search button.
  • The add-on to eliminate duplicate messages is available. Install button should be clicked.
  • Press the Restart Now button once the installation has been successful.  
  • Repeat step 3 (i.e., search for remove duplicates and hit Enter) after restarting Thunderbird.
  • Next, select My Add-Ons from the menu.
  • To remove duplicate emails, go to your account and perform a right-click on the mailbox folder (inbox, sent, drafts, etc.).
  • Select the option to Remove Duplicate Messages.
  • A notification stating that no duplicate emails were found is displayed if the chosen folder contains no duplicate emails. Press OK.
  • If there are duplicate emails in the folder, the Duplicate Messages box will open and display both the total number of duplicate emails held in the folder as well as the number of erased emails.
  • To get rid of the duplicate messages in Thunderbird, click the Delete Selected option now.
  • When confirm to approve deleting the messages, click OK.

Expert method for Eliminating duplicate emails from MBOX Mailboxes

As you can see, the manual solution is rather involved and difficult for a non-expert to understand. Additionally, the manual option is time-consuming and unsuitable for large databases because it requires you to manually choose each folder individually in order to eliminate duplicate email messages. For this reason, we have recommended MBOX Duplicate Remover, a professional solution from CubexSoft. You may quickly fix any duplicate emails from any mailbox folder and load all of Thunderbird’s mailboxes at once. Tell us how the software operates.