Desktop can't see laptop, Laptop can see Desktop (home premium network issues)

Anyone have any suggestions on how to troubleshoot a frustrating network
issue I'm having?

I have a setup with a desktop that goes straight into a router (then
out to a DSL modem) via ethernet cable -- and a laptop that connects to
the router wirelessly.

Both computers have working internet. Everything seems to be working
from the laptop to the desktop--I can browse files on the desktop and
"see" the desktop's icon/machine name in the network panel from the
laptop.

From the desktop all I can see of the laptop is is a instance of a
media player device--and even that comes and goes. I can't see the
laptop's hard drives or shared folders nor a printer I want to connect
to.

From the desktop, I can ping the laptop and get a response back which
my router company's (Zyxel) technical support says means the router is
working fine.

On both machines, I have network discovery, file sharing, public folder
sharing, printer sharing, and media sharing "On". Both machines are in
the same workgroup. What might I be missing?

Suggestions appreciated, thanks...


--
tomjonesrocks

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