Directly Convert OST to MBOX: Pro Converter & Free Methods
Fact-checked and reviewed in accordance with our Editorial Policy
BitRecover OST to MBOX Converter for Mac & Windows is an easy & fast way to bulk convert orphaned, damaged or large Outlook OST files to standard MBOX format including attachments & folder hierarchy without Microsoft Outlook or Exchange connection required for access in email clients like Thunderbird, Apple Mail, Evolution Mail, SeaMonkey etc.
Install and convert OST to MBOX files for free – demo limited to 25 items per mailbox folder.
- Save OST emails as MBOX in a 100% secure offline way with – GDPR, HIPAA & CAPA compliance.
- Export single or multiple OST files from any Outlook Version 2024, 2021, 2019, 2016 to MBOX.
- Preview OST files trees before converting to MBOX in a target based on Date Range, To, From, Subject and Exclude Folders filters.
- Save the output MBOX from OST conversion to the desired location.
Save OST data to MBOX files for free with Microsoft Marketplace approved OST to MBOX emails tool today.
In this write-up, we will discuss the complete step-by-step procedure to convert your Outlook / Exchange OST files to MBOX format using a manual solution with Outlook & email dependencies and using the pro solution.
Steps to Batch Convert OST to MBOX without Outlook
- Install and run the OST to MBOX Converter on your Mac and Windows OS.
- The software gives you the dual ways to load outlook data (OST or PST files) into the application panel i.e, Convert Configured Outlook Mailbox Data which will automatically load your source data from the default location of MS Outlook and Let me select my Outlook mailbox data that will enable the users to select OST Files / Folder manually.
- The tool allows users to export selected folder data as per requirement. User’s just need to select the required data folders.
- From the given list, you need to select the saving option to convert OST file to MBOX format.
- The software saves data to desktop location, if the users want to change the path location, simply click on the “File Browse Icon.” Now, hit the NEXT Button to transfer OST files to MBOX format.
- The software will began the process to convert OST File to MBOX format. Also, users can see the live conversion process.
- Once the conversion process get’s done users will get a success message for good.
- Here you can see your resultant MBOX files including email attachments.
Features of BitRecover OST File to MBOX Converter Tool
Using the BitRecover tool is an easy, fast and error free way convert OST to MBOX due to key features for users:
Dual OST Data Selection
- Auto-Fetch from Configures Outlook: Directly access OST files on your computer under default location – %localappdata%\Microsoft\Outlook without manual location.
- Select Files and Folders: Suited for orphaned OST to MBOX conversion in bulk.
Get Customised OST to MBOX Export
Under the “Advanced Setting” tab of the BitRecover OST to MBOX file converter, there are various filters available for selective import.
- Date Range
- From/To – Sender & Recipient Address
- Subject – Filters items based on specific keywords
- Exclude Folders – Leave out unnecessary folders like Spam, Deleted, Drafts, Newsletters etc.
- Exclude Empty Folders
OST Tree Preview Mode:
This loads the OST files in a preview only mode and lets you choose which email folders – Inbox, Sent, Other Custom Folders and other items. Users can mark or select the required folder to transfer OST files to MBOX files.
Save OST Data as MBOX With Complete Integrity
BitRecover OST to MBOX Converter preserves all emails components and map them exactly:
| Outlook Property in the OST | Where It Ends Up in the MBOX Message |
|---|---|
| Subject (PR_SUBJECT) | Subject: header |
| Sender address (PR_SENDER_EMAIL_ADDRESS) | From: header |
| HTML body (PR_BODY_HTML) | Content-Type: text/html part |
| Attachment data (PR_ATTACH_DATA_BIN) | Attachment part with Content-Disposition: attachment |
The tool preserves other header details like CC, BCC, read/unread status, flags etc.
Convert OST files to MBOX with exact folder hierarchy.
Separately Preserves OST Contacts & Calendar When Exporting to MBOX: MBOX files do not natively support Contacts and Calendars as its is natively an email format, but out tool suppose Contacts and Calendars that you can export in format like – VCF (vCard) and CSV for Contacts, and ICS (iCalendar) for Calendars
Recover Email from Supported OST as MBOX
Enable “Use Recovery Mode” to safely recover and convert corrupted OST files into MBOX with minimal errors. Moreover, the application is capable of performing entire conversion data with any error.
Track Your OST to MBOX Conversion
Monitor your conversion in real time with dynamic progress tracking, item counts, throughput speed (MB/s), and a detailed Savinglog.txt file logging all operations.
Indirect Free Method to Convert OST to MBOX Using Outlook & Thunderbird
If you have installed both Outlook and Thunderbird then you can follow manual techniques as we have shared below:
Method 1. OST to MBOX Conversion Using Thunderbird Import
- First, open Mozilla Thunderbird and click on Menu.
- Press on Tools and click on Import.
- Choose Import from Outlook and press Next.
- Select data as you want to import.
- Press on Start Import.
- Click on the Thunderbird menu again.
- Click on Add-ons and Themes.
- Search Import/Export NG Tools and click on Add to Thunderbird.
- Navigate to the mailbox folder as you want to export.
- Choose Import/Export NG Tools and click on folder export(MBOX).
- Select As MBOX file or single zipped MBOX file as per required.
- Choose the destination path and click on the select folder to successfully convert OST to MBOX.
Method 2. How to Convert OST File to MBOX Using IMAP
To perform this approach you must create a separate Gmail account as it works as a bridge. Now, follow the instructions as we have stated below:
- First, open Outlook and configure your Gmail account with it.
- Move data to the newly configured Gmail account as you want to convert OST to MBOX.
- After that, Launch Mozilla Thunderbird and configure the same Gmail account with it.
- Here, Install Import/Export NG Tools Add-ons in Thunderbird.
- Select the mailbox folder as you wish to export.
- Then, Choose Import/Export NG Tools and click on folder export(MBOX).
- Here, Select MBOX file and choose destination path.
- At last, Click on the select folder to successfully convert OST files to MBOX.
Boundaries of Manual Method
- You must have an Outlook profile configured with a healthy OST file. As this approach will not work for orphan or corrupted OST files.
- Both approaches have lengthy procedures including configuration, installation add-ons and exporting folders manually.
- It doesn’t convert calendar, contacts, tasks as it only works for emails.
- There’s no guarantee metadata will be preserved as Outlook and Thunderbird management systems are too different from each other.
- The IMAP-based method relies on syncing data through Gmail. Any disruption in connectivity can cause incomplete conversion.
Choose Best Method to Convert OST to MBOX: Key Comparison
Here is a feature comparison between multiple ways to export emails from OST files to MBOX
| Comparison Factor | Manual Methods | Free Online Converters | BitRecover OST to MBOX Converter |
|---|---|---|---|
| Outlook Installation | Yes | No | No |
| Supports Orphaned / Damaged OSTs | No | No | Yes |
| Data Size Restriction | No, but depends on Outlook and Thunderbird’s performance | Yes, generally up to 50MB – but in practical works OST files are much larger in size | No, has been tested with OST files to MBOX conversion for 100s of GB at once |
| Data Privacy & Security | Safe (Native Platforms) | No – involves data upload to third-party server | 100% Offline & Secure |
| Ease of Usage | Can be complex | No install | Requires install – easy 5 step conversion |
| Cost | Free | Free | Paid – starting at $39 – Free Trial Available before purchase |
Common Scenarios for Converting OST Files to MBOX
- If you are moving from Microsoft Outlook to Thunderbird, Apple Mail, or any MBOX supported email platform.
- OST files are linked to specific Outlook profiles and can’t be opened directly. It allows you to access the same data in a standalone email client even if Outlook is not installed.
- When an Outlook profile is deleted. If an Exchange account is deactivated, the OST file becomes orphaned; converting to MBOX allows you to retrieve and maintain data.
- MBOX files are widely supported across Windows, MacOS, and Linux. It offers greater flexibility in accessible emails into different operating systems.
- MBOX is an ideal file for long term preservation. It ensures you have a readable, portable backup of your Outlook mailbox data.
Understanding OST and MBOX & Conversion Complexities
Here is the key difference between Outlook OST files and MBOX files:
| Factor | Outlook OST | MBOX Files |
|---|---|---|
| File Extension | .ost | .mbox & sometimes exist without extension |
| Description | OST (Offline Storage Table) file is an encrypted, highly structured proprietary Microsoft database container | MBOX mailbox is a linear, open-source plain-text email message container. |
| Encoding | Internal MAPI tables, pointer indexes, and binary structures | MIME format (RFC-822 / RFC-2822), separated by the marker line |
| Related Platforms | Microsoft Outlook | Mozilla Thunderbird, Apple Mail, Eudora, Netscape, Opera Mail, or Linux Mail (Evolution, Mutt) |
| Data Stored | Emails, Contacts, Calendar, Notes, Tasks | Only Emails with Attachments & Folder Hierarchy |
| Risk of Corruption | High | Low |
OST files although enable you to access emails offline in Outlook application, they cannot be accessed outside the platform. Thus to access OST data in platforms like Thunderbird you must convert them to MBOX. Although BitRecover software and other solutions aim to minimise data loss by also separately export contacts & calendar. Certain MAPI properties cannot be preserved during conversion.
FAQs: Convert OST to MBOX
Q: Can I import resulting MBOX files from OST to Thunderbird?
Yes, the output MBOX from using the tool is compatible with multiple applications including Thunderbird, Apple Mail and other email clients.
Q: How long does it take to export OST files to MBOX files?
The time taken for conversion depends on multiple factors like – system specification, size of OST files, whether you are converting corrupted or healthy OST and which method you are using. BitRecover OST to MBOX Converter can easily convert 5 GB of OST to MBOX in easy 10 mins.
Q: Why are some emails missing during conversion from Outlook OST to MBOX?
This is because, OST file only holds what Outlook synchronized. In Cached Exchange Mode the Mail to keep offline slider decides how many months of mail are stored locally. Thus when restoring OST data in MBOX you may not see all emails that you originally found in Outlook.
Summary
In this article, we have discussed the easiest and flawless solution to export multiple outlook OST files into MBOX format. The good thing about the application is that it gives the permission to save unlimited Outlook / Exchange / IMAP .ost files to mbox format in just few simple steps. The user interface of the application is very easy, even any non-technical person can perform the conversion without any issue.
About the Author
