Outlook Office 365 for Mac

RMail for Outlook Office 365 for Mac

Track email opens, prove email delivery, encrypt private email, and get documents signed electronically — all from within Microsoft Outlook Office 365 for Mac.

For every RMail message sent, the sender is returned legal and court admissible open tracking, proof of email delivery, proof of privacy compliance, and audit-trail records for recipient electronic signatures on documents.

Main Services:

  • Track & Prove: Sends a Registered Email™ message. A Registered Receipt™ email record is then returned to the sender with court-admissible time-stamped proof of the content delivered and advanced open tracking.
  • Encrypt: Delivers files and email message body text and attachments encrypted direct to the recipient’s inbox with no need for recipients to register or click links, returning auditable proof of compliance and privacy.
  • eSign: Attach a document and send as Registered Email messages, formatted so the recipient can use their mouse to electronically draw or type their signature on the document, returning a legally signed contract to both sender and recipient

RMail is powered by RPost’s Registered Email™ technology, the global standard for email delivery proof.

Installation Tips:

Click the Getting Started button below to go to the official Microsoft app page in the Office Store to install. You will need to follow the instructions on that page to add the app to your webmail interface.

Click the Installation Guide button below to go to the RPost support center article for detailed installation instructions. This is important as the RMail Add-in gives Mac OS users three different ways to add RMail features to their outgoing Outlook mail.

  1. RMail for Outlook Online (accessible from the desktop or in browser)
  2. RMail for Outlook with Microsoft Exchange (installs into desktop email compose window)
  3. RMail Gateway (automatic encryption of email based on message content or other policies)

Product Tour

How to Install

  1. Click the “Install Now” link below
  2. In the Microsoft AppSource, click “Get it Now”
  3. Sign into Microsoft AppSource
  4. Follow the installation instructions

Install Now


Getting Started


Customer Stories

The Doctors Company

Health Tech

We’re helping The Doctors Company keep your doctor focused on cures by simplifying private communications.

Read More
Tracy-Driscoll & Co. Insurance

Insur Tech

We’re helping Tracy-Driscoll & Co. serve its clients faster, empowering staff with the best tech essentials for the business of insurance.

Read More

Legal Tech

We’re helping Airbus NH Industries’ customers defend against threats, certifying mission critical messages.

Read More

App Info



Languages Supported:

Service Language (Messages, Receipts, etc.): Danish, Dutch, English, French, German, Italian, Latvian, Lithuanian, Polish, Portuguese, Spanish.

Minimum Requirements:

Operating System Any
Browsers Any
Browser Version Latest
Deployment Single user, user group or company-wide deployment
Updates Automatic upgrades
Requirements Valid Microsoft email account. For enterprise deployments, automated deployments across multiple computers, the proper Microsoft Office 365 business license may be required. For Exchange users, there is a different user interface experience. See the Installation Guide for details.
Licensing Free for limited use, then per user, shared group of users, or usage-based
“Send Registered” Button location At the bottom of the compose page inside the menu