Office 365: In the old days, I would download an application to my PC and install it there, but I don’t understand how to add stuff to my Office 365?
You cannot install E-mail Converter directly in the Office 365 Outlook. Instead you have to install it in your desktop Outlook and use an Office 365 profile.
Please follow these steps:
Install and configure E-mail Converter in your desktop Outlook as described in the E-mail Converter manual and video demonstrations.