If you are working with workflow in AX7 then editing them requires a .NET component that will download when you start to edit the workflow. Seeing this is a download component in rare cases you might have issues with the downloaded files. If you get a message something like “application cannot be started. Contact the application vendor.” then something might have happened with the downloaded application files so you might want to clean them up.
Here is a quick overview.
AX7 Build 7.0.4230.16130
The command you see in the video is
rundll32 dfshim CleanOnlineAppCache