That’s not a URL, so it will not function as a link.
Though I’m not saying what you’re doing is a good idea (especially since there’s no link validation and moving or renaming files will break the links), a file:// URL can be used…
It’s not going to open the Finder. Windows and files will open behind DEVONthink, though Development would have to assess if the behavior could be otherwise. (And remember, we have a lot of stuff going on here, so it would be far down on the todo list.)
What is your link? Say what it is. Where is the file? Need spaces in the path? What error message might you have seen? What is “your syntax” you are referring to?
Thank you so much for your attention. I found a good way to solve this issue now.
I’ve enabling the Apple Finder feature Copy " folder/file " as Pathname and it works.
You may paste it into a targeted item as backlink as well.