The screenshots fit a network discovery and sharing configuration problem, not a mapped-drive problem. A mapped drive such as Y: can keep working even when devices do not appear consistently under File Explorer > Network.
Use this checklist on all four Windows PCs:
- Make sure all PCs are on the same network If the devices connect through a router, confirm they are all connected through that same router.
- Set the network profile to Private Microsoft’s file-sharing guidance calls this out specifically for Wi-Fi networks. Since Uranus is on Wi‑Fi, verify it is using a Private network profile.
- Turn on Network discovery and File and printer sharing
In Windows 10:
- Start > Settings > Network & internet > Sharing options
- Under Private, turn on Network discovery and File and printer sharing
- Under All Networks, turn off Password protected sharing
- Make sharing services start automatically
On the Windows 10 systems:
- Press Windows key + R
- Run
services.msc - For the sharing-related services listed in Microsoft’s guidance, open Properties, make sure they are Started, and set Startup type to Automatic
- Update Windows on all machines Microsoft recommends this as a first troubleshooting step for file-sharing issues.
- Check what is actually shared
On each PC, open File Explorer and type
\\localhostin the address bar. This shows what that computer is exposing locally. It helps confirm whether the issue is discovery, or whether the folders are not actually shared.
A few points that match the behavior shown:
- Seeing different device lists on different PCs is consistent with network discovery not being fully enabled or not working consistently on every machine.
- The NAS appearing only on Neptune under Network but still working as mapped drive
Y:is also consistent with discovery inconsistency. Discovery and direct access are not the same thing. - If the network has mixed Windows versions, Microsoft notes that putting devices in the same workgroup helps devices running different Windows versions detect and access one another.
One important limitation in the provided Microsoft content: Windows Explorer may not enumerate all computers in some environments. Microsoft documents a case where not all domain computers are listed in Explorer. That means the Network view should not be treated as a perfect inventory by itself.
Given the mix of Windows 11, Windows 10, and Windows 7, the most likely first fix path is:
- verify same network
- set every connection to Private
- enable Network discovery and File and printer sharing on every PC
- turn off Password protected sharing if that matches the intended setup
- ensure the required sharing services are running automatically
- confirm all devices are in the same workgroup
References:
- [Windows 11](https://support.microsoft.com/windows/experience/connectivity-networking/file-sharing-over-a-network-in-windows)
- [Windows 10](https://support.microsoft.com/windows/experience/connectivity-networking/file-sharing-over-a-network-in-windows)
- Set up your small business network
- Not all computers in a domain are enumerated in Windows Explorer in Windows | Microsoft Support