Outlook Addin
Contents
Outlook New/o365 web Add-In
Installation
Open your add-in marketplace 
and search for "regimail". Then follow the instructions on the screen.
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.
Functions
The regimail Add-In for Outlook new and o365 supports the following functions:
- Open and decrypt regimails and show content and extract attachments.
- Encrypt regimails from your existing email draft.
- Configure regify settings (regify account settings).
- Additional functions may be added in the future.
Compatibility notes
We tested the following combinations with the regimail Add-In (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. Now run the regimail Add-In using the "Apps" or "More Apps" button in the "Message" tab. The "encrypt now" 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/QA Version
If you like to test the beta version, you can install it from a local file only. Follow this guide:
- Right click this link regimail outlook addin beta and save the file outlook_regimail_qa.xml to your desktop or other folder (usually by right click on the link and then "Save as…").
- Click the "Apps" or "More Apps" button
in Outlook main ribbon. There, select "Get add-ins". - Click "My add-ins" on the left and remove any existing regimail add-in.
- Scroll down to "Custom add-ins" and click "Add a custom add-in" and select "Add from file…".
- Select the previously downloaded outlook_regimail_qa.xml file.
Now you see the regimail QA add-in loaded as beta version.
Outlook Classic
Compatibility Notes
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 regify Add-In for Microsoft Outlook Classic offers the following functions:
- Create and encrypt new regimails.
- Forward, Reply and Reply All using regimail.
- Reconvert regimails to ordinary emails.
- Automatically reconvert regimails while receiving.
- Configure regify settings (regify 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.
