Microsoft has deprecated support for Internet Explorer. Newer versions of Microsoft 365 running on Windows 10 now use Microsoft Edge to host add-ins, due to the deprecation of support for Internet Explorer 11 (IE11). Because of this, we no longer support the add-in hosted in IE11.
- Microsoft 365 version 16.0.11629 or greater
- Windows 10 version 1903 or greater
We'd recommend moving to an Office 365 Subscription.
Alternatively, you can use Outlook Online, which doesn’t require updates to Outlook or Windows.
See here for instructions on how to add the Actionstep Add-in in Outlook Online.