What would you mean by "still exists". I don't think this registry option really makes drives (when you wrote "driver" you probably meant "drive", right?) non-existing. It looks like it merely hides drives from the user of the Shell. Besides, the documentation describes that it is related only to drive letters. You can use a drive without a letter, as mounted to a directory. Please see:
To certain extent, it explains why the effect is manifested when you restart the explorer. I would only note that it could be not just explorer, but any other file manager or just the application using Shell API.
Another method? To start with, I would question in what sense would you need to restring the drives (volumes)? Microsoft describes the behavior of "nordives", so, in the same way, you would need to describe the behavior you want, and, importantly, explain why. And sorry, I still cannot guarantee that I would be able to answer.