It looks like Windows 10 Details tab is similar to Windows 7 Processes tab. Both have Services tab, however that’s not relevant unless you installed Duplicati as a service. Running Control Panel to see services could give you an idea of whether you installed as service. One reason to know is because:
Next thing you saw might be the failure. There’s a key part missing. What version of Duplicati is this? Looking at changelog.txt in C:\Program Files\Duplicati 2 is one way to find your base version, but you possibly have some updates over it, and the location depends on how you originally installed Duplicati.
Downgrading / reverting to a lower version gives usual update locations which depend on whether you installed as a service or not. One of these is possibly missing a CoCoL.dll file. I think an install bug can cause this if you run a Duplicati install from .msi without having first using Control Panel to uninstall the older Duplicati. You should be able to get the file by uninstalling and reinstalling the version you’re using.