Moving from External HD to NAS

Hi,
I have set up an Ubuntu NAS which is seen on the network, and on the nas based application. When opening the Windows app I cannot see the network drive or how to set up the application home page to show the NAS. I can see the Plex folder as a network drive on my PC.
Are there specific instructions for setting up a NAS? I didn't find them.
Many thanks,
Nick