.RPMSG File Extension

Restricted Permission Message File

An RPMSG file is a protected and encrypted email message created by Microsoft Outlook. The acronym "RPMSG" stands for Rights Protected Message, reflecting its primary purpose of securing email content through encryption and access controls. These files are sent as attachments to standard emails, typically using the filename "message.rpmsg".

RPMSG files were introduced as part of Microsoft's Information Rights Management (IRM) system, which has been available in Microsoft Outlook since the early 2000s. The technology evolved with Microsoft's security initiatives and became more prominent with the development of Azure Information Protection services.

When an Outlook user chooses to protect an email message:

• The content is compressed and encrypted
• Specific permissions are embedded (such as who can view, print, or forward)
• The encrypted version is saved as an RPMSG attachment
• Recipients receive a standard email containing the RPMSG attachment
• The email includes instructions and a link to open the protected content

RPMSG files serve several important purposes:

• Confidentiality: Organizations use them to share sensitive information that should only be accessible to specific recipients
• Control: Senders can restrict what recipients can do with the information (preventing forwarding, printing, or copying)
• Compliance: Many regulated industries use RPMSG to help meet legal requirements for protecting sensitive data
• Audit trails: Some implementations track who accessed protected messages and when

How to Open .RPMSG as Restricted Permission Message File

RPMSG files can be opened in several ways:

1. In Microsoft Outlook:

   • Click directly on the attachment within Outlook
   • Or select File → Open in desktop Outlook versions
   • You must be logged into the account that received the message

2. From other email clients (like Gmail):

   • Clicking the attachment redirects you to a Microsoft Outlook webpage
   • You'll need to verify your identity by signing into your email account
   • After authorization, the protected message displays in a new browser tab

3. On mobile devices:

   • Use the Microsoft Azure Information Protection app (available for Android and iOS)
   • Sign in with the account that received the protected message

How to Convert an RPMSG File

RPMSG files cannot be directly converted to other formats due to their encryption. However, once properly opened in Outlook or via the Outlook web interface, users with appropriate permissions may be able to:

• Save the contents as regular email messages (.msg)
• Copy permitted content to other applications
• Export as PDF (if printing permission is granted)
• Forward as a standard email (if forwarding permission is granted)

The conversion options depend entirely on the permissions set by the original sender. If the sender restricted copying or saving, conversion will not be possible.

Applications That Open RPMSG Files

Windows Apps for RPMSG Files:

• Microsoft Outlook Free+

macOS Apps for RPMSG Files:

• Microsoft Outlook Free+

iOS Apps for RPMSG Files:

• Microsoft Outlook Free+
• Microsoft Azure Information Protection Free

Android Apps for RPMSG Files:

• Microsoft Outlook Free+
• Microsoft Azure Information Protection Free