MacSonik OST Viewer Pro

IT Administrators

Ideal for opening, inspecting, and managing OST files across multiple users or departments during migrations, audits, or troubleshooting without requiring Microsoft Outlook.

Forensic Investigators

Enables detailed mailbox analysis by providing access to email headers, timestamps, attachments, and other metadata, making it valuable for digital forensics and internal investigations.

Business Professionals

Perfect for users who need to view, verify, and export OST mailbox data for reporting, backup, archiving, or Microsoft 365 migration without technical complexity.

Enterprise Support Teams

Helps support professionals quickly access orphaned, inaccessible, or minimally corrupted OST files to diagnose mailbox issues and reduce downtime.

Legal & Compliance Teams

Supports eDiscovery, regulatory audits, and compliance reviews by providing secure access to emails, attachments, contacts, calendars, and mailbox metadata while maintaining data integrity.

Managed Service Providers (MSPs)

A reliable solution for service providers managing client OST files for mailbox analysis, migration planning, data export, and Microsoft 365 onboarding.

Dual OST & PST Access Modes for Enterprise Control

OST File Viewer Software offers flexible mailbox loading options for enterprise users. It can automatically detect Outlook mailbox files from configured profiles or allow administrators to manually browse and load OST files from local drives, external storage, or backup locations. The software supports inaccessible, minimally corrupted, password-protected for seamless analysis.

Standalone OST & PST Viewing Without Outlook

MacSonik OST Viewing tool works independently of Microsoft Outlook, enabling users to securely open and analyze OST files without requiring an Outlook installation or Exchange connectivity. This standalone approach makes it ideal for IT administrators, legal professionals, and organizations managing archived mailbox data across multiple systems.

Comprehensive Mailbox Preview

Gain complete visibility into Outlook mailbox data with an advanced preview interface. MacSonik OST Viewer displays emails, attachments, contacts, calendars, tasks, notes, journals, and other mailbox items while preserving the original folder hierarchy and metadata, ensuring effortless navigation through large mailbox files.

Advanced Search & Smart Filtering

The MacSonik Outlook Ost Viewer quickly locates the specific emails using intelligent search capabilities. Filter mailbox items based on sender, recipient, subject, date range, or attachment status to simplify investigations, eDiscovery, and compliance-related mailbox reviews.

Detailed Email & Metadata Inspection

Analyze every aspect of an email, including message content, internet headers, MIME information, attachments, timestamps, sender and recipient details, and other metadata. This makes the software suitable for forensic investigations, legal discovery, and compliance verification.

Multiple Export & Migration Options

After previewing mailbox data, the software convert OST file to PST on Mac. Also, supports PDF, EML, MSG, MBOX, or migrate directly to Microsoft 365. The software preserves mailbox integrity, folder hierarchy, and metadata throughout the export process.

Bulk Mailbox File Analysis

Load and analyze multiple OST files simultaneously without size restrictions. This feature helps enterprises, MSPs, and IT teams process archived mailbox data efficiently during audits, migrations, or investigations.

Precision Email Export with Date Filters

Export mailbox data selectively using custom date ranges or predefined time periods. This enables organizations to migrate or archive only relevant emails while reducing processing time and storage requirements.

Resume Export with Skip Previously Exported Items

The built-in Skip/Resume feature allows interrupted export operations to continue from the last completed checkpoint. This minimizes downtime and prevents duplicate processing during large mailbox exports.

Keyword-Based Mail Filtering

Filter mailbox content using advanced conditions on To, From, Subject, or other email fields. Options such as Contains, Does Not Contain, and Match All help users export only the emails that meet specific business or compliance requirements.

Flexible Attachment Management

Choose how attachments are handled during export. Users can preserve attachments within emails, save them separately, include them on dedicated PDF pages, or exclude them entirely based on organizational requirements.

Split Large PST Files During Export

When exporting mailbox data to PST, MacSonik OST Viewing can split oversized PST files into smaller, manageable parts based on user-defined sizes in MB or GB. For PST files larger than 45 GB, the software automatically creates multiple PST files to ensure smooth data handling.

High-Quality PDF Export

Convert Outlook emails into professional PDF documents, either individually or as a merged PDF archive. The software also supports exporting attachments as separate PDF pages, making it suitable for legal documentation, records management, and long-term archiving.

Preserve Folder Hierarchy & Custom Export Location

Maintain the original mailbox structure, folder organization, email properties, and metadata throughout the export process. Users can also specify custom destination folders to keep exported mailbox data organized and easy to manage.

Comprehensive Activity & Export Logs

Generate detailed logs for every mailbox viewing, scanning, and export operation. These reports help IT teams maintain audit trails, verify completed tasks, troubleshoot issues, and support regulatory compliance.

Wide Compatibility with Free Trial

Outlook OST File Viewer supports both ANSI and Unicode along with Outlook OST files created in all major Outlook versions. Its standalone architecture eliminates the need for Microsoft Outlook installation. The free trial version allows users to preview all mailbox data and export up to 100 emails per folder for evaluation purposes.