Open MSG Files in Thunderbird

Updated on June 26, 2025 by Deepika Singh

MSG is a file extension for a mail message file created by MS Outlook Express. An MSG file can be created by dragging the file or message from Outlook folder and dropping that message on the desktop of window explorer. Now the problem arises when Outlook is not installed, and you want to open MSG file, or when you want to access that file in any other mail client which does not support MSG file format. If you want to access your MSG file in Thunderbird, you will need to migrate the file in EML/MBOX format, which is a file extension of Thunderbird.

In this page we will be discussing about how you can open your MSG files.

1. When you have both MS Outlook and Thunderbird on your system.
2. When you don’t have MS Outlook installed.

Reasons for Importing MSG Files in Thunderbird

The main reason for moving MSG files into Thunderbird accounts is that because MSG includes only a single message. It’s very difficult to handle large number of MSG files at one time.

• To open or access of multiple .msg files in your computer drive by using Thunderbird because with MS Outlook you can't access your files.
• To Convert or migrate MSG files into EML format.
• When you need to access particular files using Thunderbird, having Outlook can be inconvenient.

Steps to Open MSG files in Thunderbird Manually

Method 1: When you have both MS Outlook and Thunderbird on your system

1. Run MS Outlook, Drag and drop the message file in Outlook.
2. Click on ‘save as’ and select the location for saving the file.
3. After saving location next in ‘save as type’ select TXT as the file format and click on Save.
   
4. Then go to the file location and right click on file then from Rename change the extension from .txt to .eml
   
5. Now during conversion of file extension you will get a pop up warning prompt click Yes your file will be saved in .eml format.
   
6. Now to run the files in Thunderbird right click on the file and go to ‘open with’ option. From there select Thunderbird email application your file will be accessed in Thunderbird.

Drawbacks of Manual Method

• Requirement of both MS Outlook and Thunderbird.
• Not any security of data.
• Attachments cannot be migrated to EML file.
• This method is useful when there is less number of MSG files.

Method 2: Use Professional tool to Open MSG files in Thunderbird without Outlook

When MS Outlook is not installed on system then you have to use an alternate method i.e. by using Third Party tool to access MSG file in Thunderbird. The best software which is easy to use and will provide 100% accurate results is MSG to EML converter. This tool will help you in conversion of complete file along with attachments without any data loss and maintains hierarchy of data.

Steps to Convert MSG files to Thunderbird format-

1. Install and Run PST Converter Tool
2. Click on Browse/Add file to go to MSG files.
3. Select the files which are to be exported.
4. Take detailed Preview of the file before exporting.
5. Select the location for saving the file.
6. Next from saving option select ‘save to EML’.
7. Click Convert your file will be exported shortly.

Now reach the location where file was saved and right click on the file and Open with Thunderbird application. You will get all the data in same format as it was earlier.

Advantages of Professional tool

The Software provides many features and benefits to the users, some of them are given below:-

• The Software provides dual options where user can open single and multiple MSG folders in thunderbird at once.
• Advanced tool where you don’t need any technical skills to operate it.
• Easy to use and simple GUI Interface.
• Comes with advanced and unique features.
• Provides safe and secure MSG to Thunderbird Migration.
• The Software compatible with all the versions of Windows OS.
• Migrate MSG files to thunderbird in just few clicks.
• Migrates any size of MSG file to Thunderbird without file size limitation.

Final Conclusion:

We have discussed methods for using the MSG file in Thunderbird. The first solution is that the manual method is lengthier, less secure, and cannot be used in the absence of anyone from Outlook and Thunderbird. The first method can be used if the file number is less and does not contain any attachment. We recommend using the second method for using MSG file in Thunderbird as it is developed to overcome the limitation of the manual process. This tool will migrate the file easily and securely without taking much time.

Frequently Asked Questions

Q 1. How can I open MSG files in Thunderbird without Outlook?

Ans. You can open MSG files in Thunderbird by converting them into a compatible format like EML or MBOX. Since Thunderbird doesn’t natively support MSG, a conversion is essential.

Q 2. Can Thunderbird open MSG email files directly?

Ans. No, Thunderbird does not support MSG files natively. You need to convert them into EML or MBOX format first using a suitable conversion method or tool.

Q 3. What is the best way to convert MSG to Thunderbird-supported format?

Ans. The most efficient way is to use a professional tool like the Regain Outlook Converter Tool, which can convert MSG files to MBOX or EML formats for easy import into Thunderbird.

Q 4. How to batch convert MSG files to Thunderbird?

Ans. Use the Regain Outlook Converter Tool to convert multiple MSG files into MBOX or EML format in bulk, ensuring data integrity and folder structure.

Q 5. How do I import MSG emails into Thunderbird folders?

Ans. After converting MSG files to EML or MBOX, use the ImportExportTools NG add-on in Thunderbird to import them into the desired folder.