How to Convert OST to MBOX File?
Jackson Strong | June 3rd, 2025 | Data Conversion
Are you trying to convert OST to MBOX format? You’re not alone. Many users face this issue when they need to open OST file data in email apps like Thunderbird, Apple Mail, or others that support MBOX format, especially when the OST file is corrupted, orphaned, or inaccessible.
But finding the right solution isn’t always easy.
The problem is, OST files don’t work with MBOX email apps, and Outlook doesn’t let you export them to MBOX directly. The situation becomes even more difficult if you don’t have Outlook installed or the file is damaged.
So, how do you solve this?
In this guide, we’ll show you two easy ways:
- A manual method using Outlook and Gmail (if available).
- An automated tool i.e, Advik OST to MBOX Converter, that works without Outlook.
We’ll explain both methods step-by-step, including their pros and cons.
Let’s get started and find the best solution for your needs.
How to Convert OST to MBOX Using Thunderbird??
If you still have access to the Outlook account where the OST file is configured, you can use IMAP synchronization to transfer emails to Thunderbird and save them in MBOX format.
- Set up a Gmail Account (if you don’t have one).
- Enable IMAP Access in Gmail settings.
- Add Gmail Account to Outlook using IMAP configuration.
- Move OST Emails to the Gmail Inbox by dragging and dropping them.
- Set Up the Same Gmail Account in Thunderbird.
- In Thunderbird, move emails from the Gmail folder to Local Folders.
- The transferred emails will be stored in MBOX format.
Limitations: Time-consuming and requires manual effort.
However, if you have multiple OST files to convert, the manual method may not be the best choice. In such cases, an automated solution provides a faster and more efficient way to convert OST to MBOX. Let’s see how.
How to Convert Emails from OST to MBOX File?
If you have an orphaned OST file or need to convert OST file into MBOX quickly, using Advik OST Converter software is the best solution. With this software, you can easily convert multiple OST emails to MBOX file in one go. You can add as many OST files as needed to convert into MBOX without any extra efforts.
Also, it enables users to save messages from Outlook OST into MBOX files while preserving data integrity and mailbox folder structure. Moreover, it is an easy-to-use software that completes the whole OST to MBOX conversion process in just a few simple steps.
Give a Free try to this handy utility and export first 25 emails from each OST folder to MBOX format at no cost.
Steps to Convert OST to MBOX File
Step 1. Run the OST to MBOX Converter software and add .ost files.
Step 2. Choose the required OST mailbox folders.
Step 3. Select MBOX as a saving option from the list.
Step 4. Browse the destination path and click Convert.
The OST to MBOX conversion process has been started and you will get notified in a few seconds.
The procedure has been completed, you will be redirected to your chosen destination soon.
Once done, import the resultant file into any MBOX-supported email client.
Watch How to Export OST to MBOX with Attachments
Key Features of Advik OST to MBOX Converter
- Convert OST files to MBOX in Bulk: This OST to MBOX Tool makes converting OST emails to MBOX format simple and quick. Users can easily convert multiple OST files to MBOX at once with just a few easy steps.
- Save resultant data at the desired location: The tool allows you to set the destination path for the converted OST files using the Browse button. This feature helps users save their files in a preferred location for easy access.
- Maintains Folder Structure and Data Integrity: The tool ensures the original structure and data integrity of the OST files are maintained during conversion. Whether you are converting a few files or many, the output will be accurate and unchanged.
- Supports orphaned/Corrupted OST File: This utility effortlessly converts orphaned, corrupted, damaged, or inaccessible OST files into MBOX format without any issues. The conversion process is smooth and error-free to access items from inaccessible OST files.
- Track Live Export Status: This utility will give a live progress report. After starting the conversion process screen will show ongoing details, such as the number of files converted, files left, and export status.
- Handles Large OST Files with Ease: The tool can handle OST files of any size and convert them to MBOX without any issues. You can upload and convert large OST files quickly. It helps to convert multiple OST items without worrying about file size.
- Compatible with all Outlook and Windows OS Versions: The tool can convert OST files from all versions of Outlook, including Outlook 2021 and earlier versions. It is compatible with all the latest and previous versions of Windows OS as well.
Conclusion
Both methods help you convert OST to MBOX, but the manual way is time-consuming and limited in scope. For fast, reliable, and large-scale conversions—especially when you don’t have Outlook or face an orphaned OST—the Advik OST to MBOX Converter is the ideal solution.
Try the free demo now, export up to 25 emails per folder, and experience the full-fledged conversion tool before deciding to upgrade.
Frequently Asked Questions (FAQs)
Q1. Can I convert OST to MBOX without Outlook?
Ans. Yes! The automated tool works independently, even without Outlook installed.
Q2. Are free tools available for this conversion?
Ans. Mostly manual and tricky. The automated tool offers both a free demo and advanced features.
Q3. Will the tool keep attachments and folder structure?
Ans. Absolutely—data integrity and structure are fully preserved.
Q4. What about large or corrupted OST files?
Ans. The tool handles large and damaged OST files smoothly, converting them without errors.
Q5. Is my data safe during conversion?
Ans. Yes. The tool works locally on your PC and doesn’t upload data anywhere.
