Import MSG to Thunderbird: Convert Outlook MSG Files to EML
Importing MSG files to Thunderbird requires converting them to EML format first, since Thunderbird cannot open MSG files directly. The Turgs MSG Converter Wizard converts single or batch MSG files to EML in seconds, preserving attachments, formatting and all email headers so you can import them straight into Thunderbird.
MSG is Microsoft Outlook’s native format. Thunderbird reads EML.
They do not talk to each other directly. You cannot drag an MSG file into Thunderbird and have it work. You need a conversion step first, then a quick import into Thunderbird.
This guide walks you through how to import MSG to Thunderbird using EML as the bridge format, with step-by-step screenshots and a video walkthrough.
Why Thunderbird Cannot Open MSG Files
MSG (Outlook Message Format) stores email data in a Microsoft-proprietary binary format called CFBF (Compound File Binary Format). Thunderbird uses EML, which is a plain-text MIME format defined by RFC 822. The two formats are incompatible at the file level.
Converting MSG to EML translates the binary data into the plain-text structure Thunderbird can read. All email content transfers correctly including body text, HTML formatting, inline images and attachments.
Watch the Tutorial
[youtube https://www.youtube.com/watch?v=1Cc7nwx3IT0]
How to Convert MSG to EML for Thunderbird
Download and install the Turgs MSG Converter Wizard on your Windows PC. The free trial converts 25 MSG files per folder so you can verify the EML output before purchasing.
Step-by-Step: MSG to EML Conversion
Step 1. Launch the Turgs MSG Converter Wizard. You see the main interface with the file loading panel on the left.
Step 2. Click Add Files to add individual MSG files, or Add Folder to load an entire folder of MSG files at once.
Step 3. Your MSG files appear in the file list. Tick the checkboxes next to the files you want to convert. You can also preview email content before converting.
Step 4. From the saving options panel, select EML as the output format.
Step 5. Set the destination folder for the converted EML files and click Convert.
Step 6. When conversion is complete, a summary shows how many files were converted. Your EML files are in the destination folder.
How to Import EML Files into Thunderbird
Once you have your EML files, importing them into Thunderbird takes three steps:
- Open Thunderbird. In the left panel, click the account or folder where you want to import the emails.
- Go to Tools then ImportExportTools NG (install this free add-on from the Thunderbird Add-ons Manager first if you do not have it). If the add-on is not installed, search for “ImportExportTools NG” in the Add-ons Manager.
- Click Import EML Files and select your EML files or the folder containing them. Thunderbird imports all EML files into the selected folder.
If you do not want to install an add-on, you can also drag and drop EML files directly into an open Thunderbird folder. This works for small numbers of files but is slow for large batches.
Other MSG Conversion Formats
The Turgs MSG Converter supports more output formats than just EML. If you need to open MSG emails in a different client:
- PST: Import into Microsoft Outlook on Windows
- MBOX: Import into Apple Mail, Gmail or any MBOX-based client
- PDF: Archive individual emails as PDF documents
- HTML: Open in any browser
If you are moving in the opposite direction and need to convert OST or PST files, the guide on converting OST to MSG covers that workflow. And if you need to import into Exchange rather than Thunderbird, see the PST to Exchange migration guide.
Are you converting a small number of MSG files or migrating a full archive of thousands of messages?
Frequently Asked Questions
Can Thunderbird open MSG files directly without conversion?
No. Thunderbird does not support the MSG format natively. You need to convert MSG to EML first. The Turgs MSG Converter does this automatically in batch mode.
Will attachments be preserved when converting MSG to EML?
Yes. All attachments embedded in the MSG file are preserved in the output EML file. When you open the EML in Thunderbird, you see the attachments exactly as they appeared in Outlook.
How many MSG files can I convert at once?
The licensed version has no limit. Load an entire folder containing thousands of MSG files and the converter processes them all in a single run. The free trial converts 25 files per folder.
Does the conversion preserve email formatting?
Yes. HTML formatting, fonts, colours, tables and inline images all carry over to the EML output correctly.
Can I convert MSG files on a Mac?
The Turgs MSG Converter is Windows-only. On a Mac, the best option is to open the MSG files in Outlook for Mac and export them from there, or use a Windows virtual machine to run the converter.
What is the difference between MSG and EML format?
MSG is Microsoft’s proprietary binary email format used by Outlook for Windows. EML is the standard email format based on RFC 822, supported by Thunderbird, Apple Mail, Windows Mail and most other email clients. EML files are plain text and can be opened in a text editor, while MSG files are binary and require Outlook or a conversion tool to read.
