How to Convert OST to MBOX with CubexSoft — Step-by-Step

How to Convert OST to MBOX with CubexSoft — Step-by-Step

Overview

CubexSoft OST to MBOX is a desktop utility that converts Microsoft Outlook OST files into MBOX format used by many email clients (Thunderbird, Apple Mail, Evolution). This guide provides a concise, step-by-step workflow to convert OST to MBOX safely and preserve folders, attachments, and metadata.

Requirements

• Windows PC (CubexSoft OST to MBOX runs on Windows).
• OST file(s) you want to convert.
• Sufficient disk space for exported MBOX files.
• CubexSoft OST to MBOX installer (download from CubexSoft official site).
• Optionally: target email client (e.g., Thunderbird) for importing MBOX files.

Before you start

• Ensure the OST files are not corrupted. If Outlook shows errors, resolve them first or use a repair tool.
• Close Outlook during conversion to avoid file locks.
• If OST is from an Exchange/IMAP account and still accessible, consider exporting mail via Outlook to PST as an alternative.

Step-by-step conversion

1. Install CubexSoft OST to MBOX

   • Run the downloaded installer and follow on-screen prompts to install the software.

2. Launch the program

   • Open CubexSoft OST to MBOX from Start Menu or desktop shortcut.

3. Add OST file(s)

   • Click “Add File” or “Open” and browse to the OST file location.
   • Select one or multiple OST files. The tool will load and display mailbox folders and items in a preview pane.

4. Select folders to export

   • In the mailbox tree, checkboxes let you choose specific folders (Inbox, Sent, Contacts, Calendars may show depending on OST contents).
   • Use “Select All” if you want the entire mailbox.

5. Choose MBOX as export format

   • From the list of export options, pick “MBOX” (or “MBOX (Thunderbird)” if offered).
   • Specify whether you want a single MBOX file per mailbox or separate MBOX files per folder (if the option exists).

6. Configure advanced options (optional)

   • Apply email filters: date range, sender/recipient, subject keywords.
   • Select folder hierarchy/structure handling.
   • Preserve read/unread status, attachments, and metadata (ensure related checkboxes are enabled).
   • Set naming conventions for output files if available.

7. Select destination folder

   • Browse to or create a folder on your disk where MBOX files will be saved.
   • Ensure enough disk space and appropriate write permissions.

8. Start export

   • Click “Convert” or “Export” to begin. The program will show progress and item counts.
   • Wait until the process completes. Time depends on mailbox size and system speed.

9. Verify exported MBOX files

   • Open the destination folder and confirm MBOX files are present.
   • Optionally use an MBOX viewer or import into your email client (Thunderbird, Apple Mail) to check message integrity, attachments, dates, and folder structure.

10. Import into target client (example: Thunderbird)

• Install the ImportExportTools NG add-on in Thunderbird.
• Right-click a local folder → ImportExportTools NG → Import mbox file(s) → select files.
• Verify messages appear correctly.

Troubleshooting

• Conversion fails or stalls: restart the app, verify OST file integrity, try with a copy of the OST file.
• Missing items: check filters and folder selection; ensure OST isn’t a cached copy missing server-only items.
• Large OST: split export by folder or use filters to process in batches.

Tips & Best Practices

• Work on a copy of the OST to avoid accidental corruption.
• Keep backups before and after conversion.
• Use filters to reduce export size and time.
• Test with a small OST first to familiarize yourself with options.

Conclusion

Using CubexSoft OST to MBOX, you can reliably convert OST mailboxes to MBOX files with control over folders, filters, and metadata preservation. Follow the steps above, verify outputs, and import MBOX into your preferred mail client.