If you’ve ever tried switching from Microsoft Outlook to a different, more flexible email client like Thunderbird or Apple Mail. You may encounter a situation where you would need to convert MSG to MBOX format. This is because Outlook stores its email messages in a .msg file format. The MSG file format is not supported by many prominent email clients. Hence, you need a reliable solution to safely convert your msg files to a supported file type. This includes EML and MBOX files. That is why in this blog, we are going to explore different possible options for you to convert MSG files to MBOX format. But first, let’s understand MSG and MBOX file formats.

What Are MSG Files?

An MSG file stores a single email message from your Outlook account. It contains email details like message body, metadata (including subjects, sender, receiver, and date), and it also includes attachments. These files are often created when you export an email message from Outlook using the Drag & drop method. These Files are only supported by Microsoft Outlook and Microsoft Exchange.

What is an MBOX File?

An MBOX file is a text-based file format. Rather than storing a single message like MSG files, an MBOX file contains multiple email messages. It is used by many mainstream email clients like Thunderbird, Apple Mail, Eudora, etc. Each email is stored one after another, making it a perfect choice to archive important chats and transfer emails in bulk.

Now that we have cleared the difference between these file types. Let’s move on to the methods to convert a MSG File to MBOX format.

How to Convert MSG to MBOX Manually (Free Method)

To convert your MSG files for free, follow this manual method. It is a workaround as Outlook does not provide any native option to export emails in MBOX format. It is a lengthy process. So if you do not want to waste any time, I suggest you go straight to the next methods we have provided. But if you are confident and don’t mind getting your hands dirty, then follow carefully. This method requires many prerequisites and includes many steps.

Pre-requisites for this Method

• Microsoft Outlook
• Mozilla Thunderbird
• A little bit of technical knowledge

Step-by-Step Manual Conversion:

1. Launch Microsoft Outlook and locate the MSG file you want to convert. If the MSG file is saved separately, you can drag it into an Outlook folder to open it there.

2. Save the MSG File as a Text File
   • Click on the email to open it.
   • Go to File > Save As.
   • From the “Save as type” dropdown, choose Text Only (*.txt).
   • Save the file to your desired location.

3. Rename the .txt File to .eml
   • Go to the folder where you saved your text file.
   • Right-click the file and choose Rename.
   • Change the file extension from .txt to .eml.
   • Confirm the change when prompted.

4. Install Mozilla Thunderbird and the ImportExportTools NG Add-on
   • If you haven’t already, download and install Mozilla Thunderbird.
   • Open Thunderbird, click the menu icon (☰) > Add-ons and Themes.
   • Search for ImportExportTools NG and install it. 
   • Restart Thunderbird if needed.

5. Import EML Files into Thunderbird
   • Create a new folder inside Thunderbird where you want to import the emails.
   • Right-click the new folder and choose:
     ImportExportTools NG > Import all EML files from a directory > also from its subdirectories.
   • Select the folder containing your renamed .eml files and import them.
     
     
6. Export the Folder as an MBOX File
   • Once the EML files are imported, right-click the folder containing them.
   • Choose: ImportExportTools NG > Export Folder > As MBOX File.
   • Select a destination on your system where you want to save the MBOX file.
   • The folder’s contents will be exported and saved as a single MBOX file.

Limitations of the Manual Method

While this method doesn’t require any paid software, it comes with several drawbacks:

• The process involves many steps and switching between different applications. While converting a large number of MSG Files, it can be extremely time-intensive.
• You have to convert each MSG file individually, making it inefficient for bulk conversions.
• There is a constant risk of losing data due to honest mistakes. This can lead to corruption and loss of metadata and other details.
• Users unfamiliar with email clients, file extensions, and add-ons may find the process confusing or make mistakes during conversion.
• You must have both Microsoft Outlook and Mozilla Thunderbird installed and configured, which is not ideal for every user.

This method is best suited for users with a small number of MSG files and a good understanding of email applications. If you need to bulk export msg file to mbox format, the next method will be better suited to your needs.

Direct Method to Bulk Export MSG file to MBOX format

If you are required to convert a large number of MSG files, using dedicated software to do the job would be a clear choice for you. MSG file converter offers a reliable and quick solution. It converts MSG files to EML, MBOX, PST, and Other prominent email file formats. It reduces the risk of data corruption and damage. Unlike the above method, it does not require any complex steps and multiple software. So, let’s see how it works and convert our MSG files.

Follow these steps to convert MSG files to the desired format

1. The First Step would be to download and install the MSG File Converter.
2. Launch the Tool, then click on the Select File/Select Folder option to add the MSG files. Hit Next.
3. Here, expand the tree hierarchy structure and preview the email and attachments. Press Next.
4. Choose File Format from the drop-down list (in our case, MBOX). 
5. You can use additional features like filters to get more desired results.
6. Finally, choose a saving location by clicking on the Save to Path option and hit the Convert button.

Conclusion

This blog outlines the best approaches to convert MSG Files to MBOX Format. Based on your needs, you can choose a manual or an automated method for the job. The manual method is free but carries a lot of risk in terms of data corruption and requires a lot of time and effort. In opposition to this, an automated tool and achieve better results in less time with minimal risks. In the end, it is up to you to choose the best-suited approach for your needs.