Only 1 PC on a 3 PC Network Can See the Other 2 PCs

[esox]

Weird problem. Just built a new 2950x rig to replace an aging 5930k system. When I try to link them up on my network to transfer files, neither one detects the other. So I add an old laptop into the mix just to make sure the network is working, both the 2950x and 5930k rigs see the laptop and the laptop sees them, but the 2950x and 5930k still don't see each other. 

Got 3 PC's connected to a Hitron coda 4582 all through LAN cables. Any ideas?

***Edited Labels***

[RogersAndy]

Hey @esox!

That's certainly a conundrum! Though I don't believe it to be an unsolvable one. I had some issues with network visibility after a Windows 10 update a while back. I'm wondering if it's a similar issue. A quick checklist though to confirm:

Is everything set appropriately in Advanced Sharing Settings?
 - Network discovery and auto set up enabled
 - Sharing enabled
Is Make this PC discover-able enabled under the Network and Internet settings?
Have you tried manually adding each device to your work-group via system properties?
Is your local network setup as Public or Private?

Not sure if this helps, but perhaps others in the community may be able to shed some of their experience :).

@RogersAndy
 

[Gdkitty]

That would be my first question.. if the network sharing and discovery is on.
Usually if you open up the file browser, and then go down to network, when you go in there and it is turned off, will pop a warning up across the top to enable it.

The modem itself, should not be blocking it.

When I had that modem, i was able to connect across multiple devices to share files, etc (multiple PCs, network hard drive, etc)