Outlook Addin

Outlook New/o365 web Add-In

Installation

Open your add-in marketplace and search for "regimail". Then follow the instructions on the screen.

Compatibility notes for the regimail Outlook Add-In

We tested the following combinations on Windows 11 (December 2025):
✓ Works with O365 web (eg outlook.live.com) on Windows, MacOS and Linux. ^(c)
✓ Works with Outlook Classic 2024 with Hosted Exchange 2019 account on Windows. ^{(a) (b)}
✓ Works with Outlook Classic 2024 and O365 account on Windows. ^(a)
✓ Works with Outlook New with O365 account on Windows.
●︎ Not working with any Outlook Classic and On-Prem Exchange 2019 or 2016 backend. ^(a)
●︎ Not working with any Outlook Classic 2019 or 2016 and O365 account. ^(a)
✗ Not working with Exchange 2019 OWA (web access).
✗ Not working with Exchange 2016 OWA (web access).

(a) Consider using our regular Add-In for Outlook Classic contained in regify client setup (COM Add-In)!

(b) Due to Microsoft documentation, it works because of Outlook 2024 LTSC (volume licensing). It will not work with any previous Outlook Classic version.

(c) We've seen issues for saving decrypted regimail message attachments with Firefox browsers. If you need this, use any other up to date web browser like Edge, Chrome, Opera, Vivaldi etc.
Background: Firefox is interpreting content-security-policy values different than others. Due to this, Firefox blocks BLOB downloads because of Microsofts content-security-policy settings.

FAQ for Outlook New/o365

Q: Why don't you decrypt automatically if an encrypted regimail is received (rgf file)?
A: Office JavaScript Add-Ins cannot run code in the background or automatically when an email is selected or received. Add-In code only executes after the user explicitly opens the add-in. This is a security and performance feature of the Office platform, as documented by Microsoft. Therefore, the regimail Add-In is not able to handle regimails automatically.

Q: Why is there no regimail Add-in buttons in the Outlook GUI?
A: There are such buttons in local installed Outlook Classic 2024, but for Outlook New and o365 (in the web), the Microsoft Office Add-In API does not offer any integration into the ribbon menus. Therefore, you are forced to start the Add-In using the "Apps" or "More Apps" button to run the regimail Add-In.

Q: I wan't to reset the Add-In settings. How can I enter the settings dialog?
A: Just create a new empty email with some test subject and yourself as recipient. Now run the regimail Add-In. The "encrypt" button appears. Instead of pressing, open the hamburger menu on the upper right and navigate to settings. There, you can click the reset configuration button.

Q: I can't open a rgf file by double click?
A: This is because the Outlook API does not let us know if a user is trying to open the attached rgf file (eg double click). Therefore, the regimail Add-In unfortunately does not know. So the operating system tries to open with some installed software instead of our Add-In (which fails). Just cancel and open the rgf from the Add-In button.

Beta version

We offer you to test the new BETA regimail Add-In for Outlook New and Outlook Web (o365). If you want to install the beta version of the Add-In, please follow these steps:

Usage

Writing: During writing, the top ribbon bar is switching to "Message" view. There, you can click the "Apps" button to reach the regify Add-In for encryption. Follow the instructions on screen.

Reading: If an email is visible in preview, there appears a small "Apps" button on top of the message window. There you can reach the regify Add-In for viewing the message.

Outlook Classic

Supported versions

The current Add-In for Microsoft Outlook Classic, shipped with the current regify client setup, is available for the following versions:

• Outlook 2019 (32 Bit & 64 Bit)
• Outlook 2021 / Office 365 (32 Bit & 64 Bit)
• Outlook 2024 / Office 365 (32 Bit & 64 Bit)

Please respect that we're no longer supporting Outlook versions before 2019. Running such old e-mail client is no longer secure. Please consider upgrading to a newer version. Or how about trying Mozilla Thunderbird with its great email and calendar functions if you use IMAP or POP3 capable accounts?

Functions

The Add-In for Microsoft Outlook Classic offers the following functions:

• create new regify e-mails
• forward, reply and reply all using regify
• reconvert regify mails to ordinary e-mails
• automatically reconvert while receiving
• configure regify settings (account settings)
• invite new users to regify

Setup

The Outlook Add-In is installed automatically (in the correct version) during setup of the regify client. If you do not like to install the Outlook Add-In during setup, you can prevent it in the installer GUI. Please find additional information about setup options in the regify client deployment manual.