Simultaneous connections to one USB device

Hi there. Great piece of software you've developed! I've got a small question if you could answer it for me please.
I was able to connect a Windows machine to a USB device on a RasPi. I wanted to connect another different machine to the SAME USB device on the same Pi at the same time. When I try this, it prefixes the device in question with . When I right click on it, it displays "In use elsewhere..." at the top of the menu. Is it possible to connect multiple clients to a single USB device, whether by purchasing a license or not purchasing a license? Or is this a limitation of your software or the way that USB operates?

Many thanks,
George