OST to PST

OST to PST Converter from Aspose.Email Apps

Need to convert an OST file to PST format without installing any software or writing a single line of code? Aspose.Email free online converter is perfect for the users who need a quick and reliable way to handle Outlook data.

This is a cloud-based app that will help you recover, migrate, or restore emails with just a few clicks. The resulting PST file is fully compatible with Microsoft Outlook, email archiving systems, and .NET-based applications.

Use the OST to PST conversion method for email migration between different Outlook profiles or machines, data recovery from orphaned or corrupted OST files, archiving mailbox data. PST files can be used for programmatic email processing or mailbox automation when there is a need for integration with C#/.NET applications.

Top Features of our OST to PST Conversion App

The Aspose.Email online converter takes an Outlook offline storage file and transforms it into a personal storage file — fully compatible with Microsoft Outlook and other email clients that support the PST format. It is powered by our proven APIs and designed for performance, accuracy, and ease of use. Just upload one or more OST files, and get a PST instantly. Need to convert multiple files? No problem. The tool combines them into a ZIP archive for easy download.

One of the key features of our web app is data integrity. It preserves mailbox structure, so you can be sure that the output files can be opened in Microsoft Outlook or parsed programmatically without loss of structure or meaning. Every converted file retains folder hierarchy. It means that Inbox, Sent, Drafts, custom folders, and subfolders stay organized. All file attachments are extracted and displayed as a list. Message metadata such as To, From, Subject, Date, and other headers are kept intact. HTML content, inline images, and rich text formatting remain unchanged.

Data security is another targeted feature. The uploaded files are processed in a secure cloud environment with no third‑party access. We never view, share, or analyze your content. Each uploaded file is kept only as long as needed for processing and is deleted automatically from our servers within 24 hours. That way your sensitive data is not left online longer than necessary and is protected end to end. If you want even more control, you can use our on-premise conversion libraries. They provide APIs to integrate email processing into applications without sending data to cloud servicesj.

Before using the application, please learn about file size limits. To use the application for free, the total size of your files must not exceed 1 MB per request. For larger files (up to 5 MB), you can log in to extend the limit. If the total size of your files exceeds 5MB, please request a customised solution.

Need help? Post your question on our Aspose Support Forum — a dedicated space where developers, users, and our support team discuss solutions and best practices. The issues being discussed vary from troubleshooting file errors to learning more about working with PST files. Support is always available, and we’re constantly improving based on your feedback. Don’t hesitate to reach out — your insights help us create better solutions.