Complete OST/PST Management Toolkit
Convert, extract, and manage Microsoft Outlook OST files with ease

Created by SkyLostTR (@Keeftraum)

Version 2.1.0 - A unified Node.js application for converting, extracting, and managing Microsoft Outlook OST and PST files with UTF-8 support.

# Install globally from npm
npm install -g ost2go

# Verify installation
ost2go --version

Download pre-built binaries from Releases:

• Windows: ost2go-win.exe
• Linux: ost2go-linux
• macOS: ost2go-macos

# Windows
.\ost2go-win.exe --version

# Linux/macOS
chmod +x ost2go-linux
./ost2go-linux --version

# Clone repository
git clone https://github.com/SkyLostTR/OST2GO.git
cd OST2GO

# Install dependencies
npm install

# Install globally
npm install -g .

# Configure registry
echo "@skylosttr:registry=https://npm.pkg.github.com" >> .npmrc

# Install
npm install -g @skylosttr/ost2go

All functionality is now accessible through a single ost2go command with intuitive subcommands:

• ost2go convert - Convert OST to PST (real & legacy modes)
• ost2go extract - Extract emails to EML, MBOX, and JSON
• ost2go validate - Validate PST file integrity
• ost2go info - Display file information

npm install -g .
ost2go --help

Problem: Previous versions created PST files that crashed Outlook and Thunderbird during import.

Root Cause: The original implementation was too simplistic and didn't properly handle:

• PST header structure and format identifiers
• Block alignment and data structure compliance
• CRC checksums and file integrity validation

Solution: Completely rewritten converter with:

• ✅ Proper PST header generation with correct format identifiers
• ✅ Block-level data processing for PST compliance
• ✅ CRC32 checksum calculation for file integrity
• ✅ Advanced error handling and validation
• ✅ UTF-8 encoding preservation for international content

This is an educational/research proof-of-concept with MAJOR limitations:

• Generated PST files are NOT readable by standard PST readers (Outlook, XstReader, etc.)
• Internal structure conversion is incomplete - only header is modified
• OST database structures remain unchanged causing parse errors in PST readers
• This tool performs surface-level conversion only

OST files use proprietary Microsoft Exchange-locked database structures that are fundamentally different from PST format. True conversion requires:

• Complete B-tree database restructuring
• Node reference table rebuilding
• Block allocation table conversion
• Encryption/compression handling
• Exchange-specific metadata removal

Our tool currently only:

• ✅ Changes file header from OST to PST format
• ✅ Processes data in chunks with basic block alignment
• ❌ Does NOT convert internal database structures
• ❌ Does NOT rebuild B-tree indexes
• ❌ Does NOT handle Exchange-specific encryption

1. Microsoft Outlook Built-in Tools (RECOMMENDED):

   File → Open & Export → Import/Export → Export to a file → Outlook Data File (.pst)
   

2. Microsoft Official Utilities:

   • PST Capture tool
   • Exchange Admin Center export features
   • PowerShell Export-Mailbox cmdlets

3. Commercial Solutions:

   • Aspose.Email for .NET
   • Stellar OST to PST Converter
   • SysTools OST Recovery

This project demonstrates:

• PST/OST file format structure basics
• Node.js file processing techniques
• CLI application development patterns
• Progress tracking and error handling

📖 For detailed technical explanation of why this doesn't work, see TECHNICAL-LIMITATIONS.md

• 🔄 OST to PST Conversion: Convert Outlook OST files to PST format with improved compatibility
• 🌍 UTF-8 Support: Ensures proper encoding for international characters
• 📊 Progress Tracking: Real-time progress display during conversion
• ✅ File Validation: Validates input and output files with integrity checks
• 💻 Command Line Interface: Easy-to-use CLI with comprehensive options
• 🛠️ Advanced Error Handling: Detailed error reporting and troubleshooting
• 📁 PST Format Compliance: Proper header structure and block alignment
• � Standalone Binaries: No Node.js required for end users
• � Multiple Distribution Channels: npm, GitHub Packages, and standalone binaries

# Extract emails to EML, MBOX, and JSON formats
ost2go extract -i input.ost -o my-emails --max 100

# Extract with verbose output
ost2go extract -i input.ost -o my-emails --max 500 --verbose

# RECOMMENDED: Real converter (extracts actual emails)
ost2go convert -i input.ost -o output.pst --real --max-emails 100

# Legacy converter (educational only - output not readable)
ost2go convert -i input.ost -o output.pst --force

# Validate a PST file
ost2go validate -i output.pst

# Validate with detailed output
ost2go validate -i output.pst --verbose

# Display OST file information
ost2go info -i input.ost

📚 For comprehensive documentation, see OST2GO_GUIDE.md

• -i, --input <path>: Input OST file path (required)
• -o, --output <path>: Output PST file path (required)
• --utf8: Ensure UTF-8 encoding support (default: true)
• --overwrite: Overwrite output file if it exists (default: false)
• --force: Skip format compatibility warnings (default: false)
• --real: Use real converter to extract actual emails (recommended)
• --max-emails <number>: Maximum number of emails to convert (default: 100)

• -i, --input <path>: PST file path to validate (required)
• --verbose: Show detailed validation information

• -i, --input <path>: Input OST file path (required)

# Convert a typical OST file (with compatibility warning)
node src/index.js convert -i "C:\Users\John\Documents\Outlook Files\archive.ost" -o "C:\Users\John\Documents\Outlook Files\archive.pst"

# Get information about an OST file
node src/index.js info -i "C:\Users\John\Documents\Outlook Files\archive.ost"

# Convert with overwrite enabled and skip warnings
node src/index.js convert -i "./input.ost" -o "./output.pst" --overwrite --force

# Test conversion with a small file first
node src/index.js convert -i "small_test.ost" -o "test_output.pst" --force

1. Try a smaller test file first:

   # Create a test with a portion of your OST
   node src/index.js convert -i "small_sample.ost" -o "test.pst" --force

2. 🏢 Use Microsoft's official tools:

   • Open Outlook
   • Go to File → Open & Export → Import/Export
   • Choose "Export to a file" → "Outlook Data File (.pst)"

3. Check file integrity:

   # Get file information to verify the conversion
   node src/index.js info -i "converted_file.pst"

4. Import gradually:

   • Import only a few folders at a time
   • Check for specific problematic emails or attachments

npm test

npm run dev

• OST files: Offline Storage Table files used by Outlook for cached email data
• PST files: Personal Storage Table files used for archiving and backup
• Both formats share similar internal structure but have different headers and metadata

The converter ensures that text content within emails maintains proper UTF-8 encoding, which is essential for:

• International characters (á, é, í, ó, ú, ñ, etc.)
• Emoji and special symbols
• Multi-language email content

The converter processes files in chunks to handle large OST files efficiently:

• Default chunk size: 1MB
• Progress tracking for large files
• Memory-efficient streaming

This is a proof-of-concept implementation for educational purposes. The actual OST/PST file formats are proprietary Microsoft formats with complex internal structures. For production use, consider:

1. 🏢 Microsoft's official tools: Use Outlook's built-in import/export functionality
2. 💼 Professional libraries: Consider commercial solutions like Aspose.Email or similar
3. 🖥️ Exchange Server: Use server-side conversion tools when available

• This implementation provides a basic framework but may not handle all OST format variations
• Complex email attachments, calendar items, and advanced features may require additional processing
• Microsoft's PST format has evolved over different Outlook versions (97, 2003, 2007+)

• Ensure you have proper rights to convert OST files
• Respect data privacy and corporate policies
• Consider encryption and security requirements

ost-to-pst-converter/
├── 📁 src/
│   ├── 📄 index.js                 # Main CLI application
│   └── 📁 converter/
│       └── 📄 OstToPstConverter.js # Core conversion logic
├── 📁 test/
│   └── 📄 test.js                  # Test suite
├── 📄 package.json                 # Project dependencies and scripts
└── 📄 README.md                   # This file

1. 🍴 Fork the repository
2. 🌿 Create a feature branch
3. ✏️ Make your changes
4. 🧪 Run tests: npm test
5. 📤 Submit a pull request

This project is licensed under a proprietary license - see the LICENSE file for details.

For issues and questions:

1. 🔍 Check the troubleshooting section below
2. 🧪 Review the test results with npm test
3. 🔧 Ensure your Node.js version is 16+

1. "Input file does not exist"

   • Verify the file path is correct
   • Use absolute paths when possible
   • Check file permissions

2. "Output file already exists"

   • Use the --overwrite flag to replace existing files
   • Choose a different output path

3. "Conversion failed"

   • Ensure the input file is a valid OST file
   • Check available disk space
   • Verify file is not corrupted or locked by Outlook

4. "UTF-8 encoding issues"

   • The converter attempts to handle encoding automatically
   • For complex encoding issues, consider professional tools

• Close Outlook before converting OST files
• Ensure sufficient disk space (PST files can be similar size to OST)
• Use SSD storage for better performance with large files
• Consider converting large files in smaller segments if needed

This project is licensed under a proprietary license - see the LICENSE file for details.

OST2GO is created and maintained by SkyLostTR (@Keeftraum)

• GitHub: https://github.com/SkyLostTR/OST2GO
• Issues: https://github.com/SkyLostTR/OST2GO/issues
• Discussions: https://github.com/SkyLostTR/OST2GO/discussions

OST2GO v2.0.0 - Complete OST/PST Management Toolkit
Built with ❤️ by SkyLostTR (@Keeftraum)