Installation of the IncaMail Add-Ins

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Installation of the IncaMail Add-Ins

Updated August 05, 2026 11:48

Accepted Answer

Types of IncaMail Add-Ins for Outlook

HTML Add-In for Outlook Desktop and Outlook on the Web (recommended)

The HTML Add-In is based on the latest Microsoft Add-In technology and requires Outlook version 2016 or later. In addition to sending IncaMail messages in three sending modes, it also supports sending large files up to 1 GB, as well as the logbook with the protocol of all IncaMail messages and a secure recall option. The HTML Add-In also works in Outlook on the Web on Apple Mac and Linux computers.

COM Add-In for Outlook

The COM Add-In is available for all Outlook desktop versions for Windows from Outlook 2007 up to and including Outlook 2019 (32 and 64 bit). It is limited to sending messages in the sending modes Confidential, Personal, and Registered. This Add-In is only supported in “Classic” Outlook and cannot be used in “New” Outlook.

Prerequisites for Using the Add-In

Both Add-Ins work with both on-premises Exchange servers (servers in your own IT infrastructure) and cloud Exchange servers (e.g., with a provider or in the case of Microsoft 365 at Microsoft). For HTML Add-Ins, Exchange version 2016 or later is required.

Important: IncaMail requires that the mail server infrastructure for incoming and outgoing emails is protected by valid TLS certificates from a recognized CA (Certificate Authority). For IncaMail customers, such certificates are available at a discounted rate from the Swiss provider SwissSign.

A business customer contract must be concluded for IncaMail for the mail client. This is possible online.

Installation of the IncaMail Add-In

In companies, installation is usually done centrally by Exchange/Outlook administrators. With appropriate local admin rights, installation can also be performed by the end user. Depending on your Outlook version, the installation steps may look slightly different.

HTML Add-In Desktop
HTML Add-In OWA
COM Add-In

The COM Add-In is delivered as an MSI installation package and can be started directly in Windows. You can find it on our download page. Please note that for 32-bit versions of Outlook/Office, you must also install the 32-bit version of the COM Add-In, and for the 64-bit version of Office, the 64-bit version of the COM Add-In accordingly.

Start Outlook and click on the Manage Add-Ins icon in the File menu (not Manage COM Add-Ins).
Open the link Manage My Add-Ins. The browser will open. Sign in with your Outlook account.
Look for Custom Add-Ins and then Add Custom Add-In / Add from URL. Insert one of the following links and confirm with Next and Install:
- HTML Add-In with IncaMail Large File Transfer: https://addins.incamail.com/app/incapac/manifest-incamail.xml
- HTML Add-In without IncaMail Large File Transfer: https://addins.incamail.com/app/incapac/manifest-incamail-cpr.xml
If the option Add from URL is not displayed, download the required Add-In file (XML file) from the download page and save it locally.
Perform the above steps again to reopen the Add-Ins window for Outlook if necessary, and select Add from File instead of Add from URL. Then select the XML file you saved in the previous step, click Open, and confirm with Install.
If you see an icon for All Apps instead of the Add-Ins icon, open this URL in your browser: https://aka.ms/olksideload and continue with Step 3.

Start Outlook in your browser.
Look in the ribbon for Get Add-Ins or in a message menu under …/Get Add-Ins.
Look for Custom Add-Ins and then Add Custom Add-In / Add from URL. Insert one of the following links and confirm with Next and Install:
- HTML Add-In with IncaMail Large File Transfer: https://addins.incamail.com/app/incapac/manifest-incamail.xml
- HTML Add-In without IncaMail Large File Transfer: https://addins.incamail.com/app/incapac/manifest-incamail-cpr.xml
If the option Add from URL is not displayed, download the required Add-In file (XML file) from the download page and save it locally.
Perform the above steps again to reopen the Add-Ins window for Outlook if necessary, and select Add from File instead of Add from URL. Then select the XML file you saved in the previous step, click Open, and confirm with Install.
If you see an icon for All Apps instead of the Add-Ins icon, open this URL in your browser: https://aka.ms/olksideload and continue with Step 3.