Can I use importfile() to pull in a local file instead of web file?

I'm trying to use

importFile(this, "file:///users/....") . to add a file as an attachment without luck (on a mac)

Does file:/// work?  - all the examples I found use http: instead - wondering if I can pull in a local file?

Ninox Profile

This will not work in the Mac-enviroment.