Convert PST to RPMSG

Understanding PST and RPMSG file formats

PST (Personal Storage Table) is a file format used by Microsoft Outlook to store copies of messages, calendar events, and other items. It is commonly used for archiving and backing up Outlook data.

RPMSG (Restricted Permission Message) is a file format used by Microsoft Outlook and Exchange to deliver rights-protected email messages. These messages use Information Rights Management (IRM) to restrict actions such as forwarding, copying, or printing.

Why convert PST to RPMSG?

Converting PST to RPMSG is typically required when you need to apply rights management protection to emails stored in a PST file. This ensures sensitive information is protected and access is controlled according to organizational policies.

How to convert PST to RPMSG

There is no direct, automated tool that converts an entire PST file to RPMSG format, as RPMSG is not a general email storage format but a rights-protected message format. However, you can achieve this by exporting emails from PST and then applying IRM protection to individual messages.

1. Open Microsoft Outlook and load your PST file via File → Open & Export → Open Outlook Data File.
2. Select the email you want to protect.
3. Go to File → Info → Set Permissions or use the Options → Permissions button in the message window.
4. Choose the appropriate rights management template (e.g., Do Not Forward).
5. Send or save the message. Outlook will convert the email to RPMSG format.

To automate this process for multiple emails, consider using Microsoft Power Automate or custom scripts with Outlook API, but manual intervention is usually required for rights management application.

Best software for PST to RPMSG conversion

• Microsoft Outlook – The only reliable way to apply IRM and generate RPMSG files.
• Microsoft 365 (Exchange Online) – For organizations, IRM policies can be applied automatically to emails via mail flow rules.

There are no third-party converters that directly convert PST files to RPMSG due to the proprietary and secure nature of the RPMSG format.

Summary

While you cannot directly convert a PST file to RPMSG, you can export emails from PST and apply IRM protection using Microsoft Outlook, which will create RPMSG files. For bulk operations, enterprise solutions like Microsoft 365 with IRM policies are recommended.