Convert OST to EML
Online Tool

OST (Offline Storage Table) is the file format used by Microsoft Outlook (Exchange cache). It stores email messages along with their metadata, attachments, and folder structure.

OST files are commonly encountered when:
- Migrating between email platforms — switching from Microsoft Outlook (Exchange cache) to another system
- Email archiving — long-term storage of email communications
- Legal and compliance — eDiscovery and regulatory requirements
- Backup and recovery — protecting email data from loss

While OST is widely used in its native ecosystem, working with these files outside of Microsoft Outlook (Exchange cache) can be challenging without proper conversion tools.

Converting OST to EML is essential in several scenarios:

1. Migrating to Windows Mail, Thunderbird, most clients
If you're moving to Windows Mail, Thunderbird, most clients, converting OST to EML allows you to import your entire email archive with folder structure and metadata preserved.

2. Cross-platform access
OST files require Microsoft Outlook (Exchange cache) to open natively. Converting to EML makes your emails accessible on Any OS.

3. Email archiving and compliance
Organizations often need to convert email archives between formats for legal discovery, compliance requirements, or long-term storage strategies.

4. Opening emails without Microsoft Outlook (Exchange cache)
If you receive a OST file but don't have Microsoft Outlook (Exchange cache), converting to EML lets you access the emails in Windows Mail, Thunderbird, most clients or any compatible client.