Currently when you install Outlook, it defaults to the 64-bit version Aid4Mail version 4 actually runs smoother and faster with the 32-bit Outlook version. We would highly recommend that you use the 32-bit Outlook version if you will be using Aid4Mail to mainly migrate/convert Outlook email profiles or PST and MSG file types.
Here is further information from Microsoft about the differences between the 64-bit and 32-bit versions of Outlook:
Instructions on how to install the 32-bit version are also in the above help article.
If you experience any issues, please don't hesitate to contact us by raising a ticket.