How to move Thunderbird mails to Outlook 2019

Mozilla Thunderbird is an open-source, cross-platform email client which stores all email data in an MBOX file. On the other hand, Microsoft Outlook uses a different file format (PST) to store email data. Though Thunderbird email client allows you to import messages from Outlook Express, vice-versa is not supported.

If you are using Outlook 2019 and want to move your Thunderbird emails to it, there is no direct way, as Outlook does not support the MBOX file format. However, with the help of a few manual and automated methods, you can complete the migration without much hassle.

Let’s explore two different methods to move Thunderbird emails to Outlook 2019.

Method 1: Use a reliable MBOX to PST Converter

As the title suggests, this method uses a commercial product to convert MBOX file into PST which can be imported in Outlook 2019. The solution is divided into three phases detailed below.

Phase 1 – Export MBOX file from Thunderbird

1. Open Thunderbird email client
2. Click on the bar icon and then click on Add-Ons menu
3. You will see a new window appear on the screen. Click Up & Coming option
4. Search Import/Export plug-in. Download and install the plug-in
5. Restart Thunderbird
6. Go to mailbox and right click on All Mail option
7. Select ImportExportTools and then click Export Folder
8. Select the location where you want to export MBOX file
9. Open the desired location that contains all mail files
10. Right-click on the file and add .mbox extension

Now all your Thunderbird emails are available in one MBOX file. Since Outlook does not support MBOX file format, you need to convert MBOX file into PST file. This can be achieved with the help of a competent MBOX to PST Converter.

While there are several MBOX to PST converters available online, the most proficient and risk-free converter for the purpose is Stellar Converter for MBOX. Extending support for over 17 MBOX email clients, this software can migrate multiple mailboxes in one go. You can save the converted data as a new PST file or append it to an existing PST and even preview the items before saving them. The tool is compatible with all Outlook versions, from Outlook 2003 through Outlook 2019. The tech version of the product lets you save the converted emails in many other formats like Office 365, HTML, PDF, RTF, etc.

Now let’s see how this product can be used to convert MBOX to PST.

Phase 2 – Convert MBOX to PST

1. Install Stellar Converter for MBOX on your Windows PC
2. Launch the software and from the home page, select the source mailbox client
3. Now, select the MBOX file to convert. You can select a single or multiple files.
4. Once the mailbox file has been scanned, you can preview converted items before saving.
5. When ready to save, click on the ‘Save’ button from the menu, select output as PST (new or existing), and select desired output folder (where you want the PST file saved)
6. Wait for the conversion process to complete. The software will display a notification when the conversion process is completed successfully.

Once the MBOX file has been converted to PST format, all you have to do is import the PST file into Outlook 2019 to access all your mailbox information.

Phase 3 – Import PST file into Outlook 2019

1. Open Outlook 2019 on your system
2. Click File and then click Open & Export
3. Click Import/Export and then select Import from another program or file
4. Click Outlook data file (.pst) and then Click Browse
5. Navigate to the folder where the converted PST file is located and select it
6. Select Account and then click Finish

This is one way of completing MBOX to PST conversion in an easy and efficient manner. Now let’s cover the manual method of performing the conversion, which is free of cost but is also a lot slower and risk prone.

Method 2: Save MBOX mails as EML files and then convert them to PST format

Though MS Outlook does not support MBOX file format, it does support EML files. EML is a file extension for an e-mail message used by Microsoft Outlook Express. The EML file contains plain ASCII text for the main message body and headers. It also supports hyperlinks and attachments.

Here’s how you can convert MBOX data to EML format.

Phase 1 – Export Thunderbird mails as EML files

You can export Thunderbird mails as EML files in two different ways. The first method uses the “Save as” option while the second method use “Save selected messages” option

Using “Save as” option

1. Open Mozilla Thunderbird email client on your PC
2. Select all emails (Press Ctrl+A to select all messages of current folder) which you want to export as EML files
3. Right-click on selected mails and click Save as option
4. Navigate to the folder where you want to export mails as EML files
5. Now, click Select Folder

Use “Save selected messages” option

1. Launch Mozilla Thunderbird email client
2. Press Ctrl+A to select all messages of current folder which you want to export as EML files
3. Press right-click on selected messages and click Save selected messages
4. Click EML format
5. Browse to the folder where you want to save EML files.
6. Select the folder and then click Select folder button to confirm your selection
7. Wait for the export mail process to complete.

Phase 2 – Drag and drop EML files to Outlook folder

1. Open the folder where all your EML files are saved
2. Drag and drop all EML files into an Outlook folder on your PC.

Phase 3 – Export emails to PST files

1. Launch Outlook 2019
2. Click File menu
3. Click Open and Export and then click Import/Export
4. In the Import/Export wizard window, select Export to a file and click Next
5. In the next window, select Outlook Data File (.pst) and then click Next
6. Go to the folder where EML files are saved. Make sure the subfolders box is checked
7. Click Next
8. Input a new location to save the new PST file that will be created. Choose any desired options under heading Options
9. Click Finish
10. Now Outlook 2019 will create a new PST file. Wait for the process to complete

Phase 4 – Import PST file into Outlook 2019

1. Launch Outlook 2019 on your system
2. Click File from the Outlook ribbon
3. Click Open and Export and then click Import/Export
4. In the Import/Export wizard window, select Import from another program or file and click Next
5. In the next window, click Browse to the pst file you want to import
6. Under options, select any desired option and click Next
7. In the next window, select the folder to import from
8. Choose option Import items into the same folder
9. Click Finish

You can see the progress of import activity in a dialog box. When the pop-up disappears, it indicates that the process of importing PST file is completed.

Wrapping it up

You can use any of the above-mentioned methods to move Thunderbird mails to Outlook 2019. Large files are prone to corruption during conversion so make sure you divide the moving of mail into small batches or use an automated converter. Before starting with the conversion, backup your MBOX file so that you can restore the data if needed.