Read time 6 minutes

Summary: This article discusses the process of migrating data from Eudora to Thunderbird email clients. It covers locating the Eudora mailbox file, manual migration steps using Thunderbird’s ImportExport add-on, and introduces a third-party tool, Kernel MBOX Viewer, for easier data access.

Eudora and Thunderbird stand out as remarkable email clients, offering a rich array of features and functionalities. Nevertheless, Thunderbird often enjoys a preference among users for several reasons, including its open-source nature, free availability, and user-friendly interface. For those contemplating a shift from Eudora to Thunderbird, it’s essential to have a clear understanding of the methods required to migrate data between these two clients. In this article, we will explore solutions for seamlessly importing emails and other mailbox data from Eudora into Thunderbird.

To begin, you must locate the precise directory of Eudora Mail’s MBX file within your system. Generally, for Eudora 8 installations on Windows 10 and 8 operating systems, the default location of the source database file (MBX) is as follows:


If you’ve manually specified the mailbox directory when setting up Eudora on your system, it’s straightforward to pinpoint the precise location of the MBX file. If, however, you’re having trouble locating the source database file, you can resolve this by opening Eudora and following these steps: Go to the “Tools” menu, then select “Account Settings,” and finally, navigate to the “Message Storage” section.

locate the source database file

Note: Eudora Mail stores its data using the MBX file format, which is a variation of the MBOX file format.
After obtaining the source database file, your next step is simply to import the MBX file into the Thunderbird client.

Manual Approach to Import Data from Eudora to Thunderbird

To import external MBOX files into Thunderbird, you’ll need to install the “ImportExport” add-on. Follow the provided instructions to both add the ImportExport extension and import the necessary MBOX files.

  1. Open Thunderbird and select the Menu button positioned at the far right of the interface.
  2. Select “Add-ons” from the menu and then click on “Add-ons.”
  3. Within the Add-ons Manager window, locate the ImportExport add-on. Next, opt for ImportExportTools NG and press the Add to Thunderbird button.
    Add to Thunderbird button
  4. A message will prompt you to install the ImportExportTools NG add-on in your Thunderbird client. Simply click the Add button, and then restart the program to apply the changes.
    add the ImportExportTools NG
  5. Return to the Thunderbird mailbox window, and perform a right-click action on the main node within the Local Folders hierarchy. From the dropdown menu, opt for ImportExportTools NG >> Import mbox file.
    select ImportExportTools NG and Import mbox file
  6. Select the “Import one or more mbox files directly” option and then click “OK.”
    Import directly one or more mbox files
  7. Navigate to the directory where Eudora’s source database file (MBOX) is located, choose the necessary files, and then press the “Open” button.
    click Open
  8. Once more, return to the Thunderbird mailbox window and select the imported file to access its email contents.
    click on the imported file

Apart from the manual procedure to import Eudora to Thunderbird, you can also use third-party tools to view email contents of MBOX files or its variants. We have also highlighted an efficient third-party software “Kernel MBOX Viewer” designed specifically to import data from MBOX format files that are based on all major email client applications.

Introducing Kernel MBOX Viewer, a versatile software application designed for hassle-free access to MBOX files, all without the need for a dedicated MBOX email client. This user-friendly tool comes equipped with intuitive email filters and boasts compatibility with MBOX files originating from popular email clients such as Thunderbird, Apple Mail, Eudora, Entourage, and more. Furthermore, you can effortlessly import multiple MBOX files of any size, without encountering any limitations. Allow us to elucidate how this remarkable tool operates:

  1. Open Kernel MBOX Viewer on your computer and choose the email client source. Then, click the Next button.
    click on the Next button
  2. Click on the Add File(s) button to locate the required MBOX file on your local directories.
    Click on the Add File
  3. Choose the necessary MBOX files and then press the “Open” button.
    click Open
  4. After incorporating the files into the interface, proceed by selecting the Finish button.
    click on the Finish button
  5. In the upcoming window, choose a specific mailbox folder from the left-hand side panel to access its email contents.
    select an individual mailbox folder from the left-hand side panel

Wrapping Up

Eudora users will discover this article to be exceptionally valuable, as it outlines the process of accessing and transferring data files to the Thunderbird email platform. This enables users to harness the features of the new platform while safeguarding their original data from their Eudora account. For enhanced data security and the efficient transfer of large datasets, consider using the Kernel MBOX Viewer software to review the contents of your Eudora files prior to migrating them to Thunderbird.

Kernel for MBOX to PST