How to Merge / Convert Outlook MSG to MBOX File in Batch ?
MSG is the Outlook email format. MBOX is the format used by Thunderbird, Apple Mail and other Unix-based email clients. To convert MSG files to MBOX, use Turgs MSG Converter Wizard on Windows. It converts single or batch MSG files to MBOX in a few minutes and preserves all email properties and attachments.
Outlook saves individual emails as MSG files. MBOX is the standard mailbox format used by Thunderbird, Apple Mail and most Unix-based email clients. If you are switching from Outlook to Thunderbird or another MBOX-compatible client, you need to convert your MSG files to MBOX format. This guide shows you how to do it in batch on Windows.
Why Convert MSG to MBOX?
MSG files are a proprietary Microsoft format. They can only be opened natively in Outlook. MBOX, by contrast, is an open standard supported by dozens of email clients including Thunderbird, Apple Mail, The Bat, Evolution and many others.
The most common reasons to convert MSG to MBOX include migrating from Outlook to Thunderbird, importing archived Outlook emails into Apple Mail, sharing email archives with users on non-Windows systems and preserving email records in a portable, open format that does not depend on Microsoft software to open.
If you have 500 MSG files, opening each one in Outlook and re-exporting as EML or MBOX individually takes hours. A batch converter processes all 500 in a few minutes with no manual steps per file.
The tool I recommend is Turgs MSG Converter Wizard. It converts MSG files to MBOX and 15+ other formats in batch, preserves all email properties and works without Outlook installed on the conversion machine. For MBOX-related conversions, also see Turgs MBOX Converter Tool.
How to Convert MSG to MBOX Step by Step
Follow these steps to batch convert MSG files to MBOX. The process typically takes 2 to 5 minutes for a folder of 100 MSG files.
Step 1: Download and install Turgs MSG Converter Wizard on your Windows PC.
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Step 2: Launch the tool. Use the Add Files or Add Folders options to load your MSG files. The dual selection lets you mix individual files and entire folders in one batch.
Step 3: The tool loads and previews your MSG emails. Click any email to see a full preview of its content before converting. This confirms the correct files are loaded.
Step 4: Select MBOX from the saving options list. The tool will merge all selected MSG files into a single MBOX file by default, which is how most MBOX-based clients expect to import mail.
Step 5: Set the destination folder where the MBOX output file will be saved. Choose a location with enough free space. A 500-MSG batch averages about 50 to 200 MB as MBOX depending on attachment sizes.
Step 6: Click Convert. The tool processes all MSG files and creates the MBOX output. A real-time progress counter shows completion status.
Once done, import the MBOX file into Thunderbird via Tools then Import, or into Apple Mail via File then Import Mailboxes. Your converted emails will appear in the client’s folder structure.
Key Features of the MSG to MBOX Converter
Here is what makes this tool the right choice for MSG to MBOX conversions.
- Batch conversion: Convert hundreds of MSG files at once using the dual file and folder selection. No per-file manual steps required.
- Email preview before conversion: View the content of any MSG file in the interface before running the conversion. Useful for confirming the correct files are loaded.
- Email properties preserved: Sender, recipient, CC, BCC, subject lines, timestamps and attachments all carry over to the MBOX output.
- Multiple output formats: Beyond MBOX, the tool converts MSG to EML, PST, PDF, HTML, DOC, CSV, EMLX and more. One tool handles all MSG conversion needs.
- No Outlook required: The tool reads MSG files directly without needing Outlook installed. Convert files on any Windows machine.
- All Windows versions supported: Works on Windows 11, 10, 8.1, 8, 7 and Windows Server editions.
Limitations to Know
Limitations
- Windows only: No Mac or Linux version is available.
- Free trial limitation: The trial converts a limited number of MSG files per batch. A full license is required for unlimited conversions.
- MBOX import depends on the client: After converting, you still need to import the MBOX file into your target email client. The import steps vary by client but are generally straightforward.
- Very large MSG files take longer: MSG files with large attachments (over 10 MB per file) can slow the conversion process on older hardware.
- Single MBOX output by default: The tool merges all MSG files into one MBOX file. If you need separate MBOX files per folder, organize your MSG files into subfolders before running the converter.
Frequently Asked Questions
Can I convert MSG to MBOX without Outlook installed?
Yes. Turgs MSG Converter Wizard reads MSG files directly without needing Outlook. This is especially useful when you are migrating on a machine that never had Outlook, or when processing MSG archives received from another user.
How do I import the converted MBOX file into Thunderbird?
In Thunderbird, go to Tools then Import. Select Mail from an application and choose MBOX as the format. Browse to the converted MBOX file and click Open. Thunderbird imports all emails from the MBOX file into a new folder in your local folders.
Will email attachments be preserved in the MBOX output?
Yes. All attachments from the original MSG files are preserved in the MBOX output. When you import the MBOX into Thunderbird or Apple Mail, all attachments are accessible directly from the imported emails.
Can I convert a large batch of MSG files at once?
Yes. The dual file and folder selection lets you add thousands of MSG files at once. The tool processes all of them in a single run. Actual processing speed depends on the size of the files and your hardware, but 500 standard emails typically convert in 3 to 5 minutes.
Does the converted MBOX file work with Apple Mail?
Yes. Apple Mail supports MBOX import on macOS. In Apple Mail, go to File then Import Mailboxes. Select MBOX files and browse to the converted MBOX file. Apple Mail imports all emails into a new mailbox folder.
Can I also convert MBOX files back to MSG format?
Yes, though that requires a different tool. Turgs MBOX Converter can convert MBOX files to MSG and PST format. If you need to go in the other direction, check the Turgs MBOX Converter Tool page for the exact steps.
