After I allowed my Lenovo laptop to upgrade from Windows 7 to Windows 10, ver 1511, the laptop could no longer see most other computers, or any NAS devices on my home network. It could see one Windows 7 computer (sometimes) and my brother’s laptop (sometimes) but that was all. It could not see my three NAS devices, nor my XP computers, nor my Ethernet/USB print server.
Summary: I renamed my Workgroup from its original 5-character name, “WALSH”, to a workgroup name with 7 characters “WALSH01”, or “WALSHES” and suddenly the Windows 10 machine could see my other devices under Network in File Explorer.
After I upgraded my Lenovo laptop from Windows 7 to Windows 10 ver 1511, the laptop could no longer see most other computers, or any NAS devices on my home network. It could see one Windows 7 computer (sometimes, but not reliably), and my brother’s laptop (also sometimes, but not reliably), but that was all. It could not see any of my three NAS devices, nor my XP computers, nor my Ethernet/USB print server.
I tried many suggested solution on the internet, but none of them worked.
I reverted back to Windows 7 and I could see my network again. That told me that my network was basically sound.
In order to start from a known clean state, I did a clean re-installation of Windows 7 Pro from Recovery DVDs, and let Windows 7 apply all the relevant upgrades. At this stage my Lenovo laptop could see all the devices on my network which consisted of 2 x Win XP computers, one Linux computer, one Win 10 computer, one Win 7 computer, three NAS devices, and an Ethernet/USB print server.
I then let my laptop upgrade to Windows 10.
After the upgrade, I checked File Explorer > Network (neighbourhood), but the laptop could NOT see any other devices except the other Win 10 computer (sometimes, but not reliably), and the Win 7 computer (also sometimes it would show up but not reliably). No other devices were visible.
I searched internet forums for days and tried many suggested solutions, none of which worked, and some were just not applicable.
After many frustrating hours I tried renaming my workgroup to something different.
My workgroup had been named WALSH, so I renamed it to WALSH01 for the laptop and WALSH01 for one of the NAS devices. I rebooted both, and Windows 10 was suddenly able to see the NAS device under Network in File Explorer. As a trial I renamed the workgroup back to WALSH for the laptop and the NAS device, and File Explorer could no longer see it.
I repeated this procedure twice more with consistent results each time; that is, when the Win 10 laptop’s workgroup, and the NAS device’s workgroup name was WALSH the laptop COULD NOT see the NAS device, but when I name them to WALSH01, the laptop could see the NAS device.
I did another test by renaming the workgroup to WALSHES for both the laptop and the NAS device, and the laptop could see the NAS device under Network neighbourhood when the workgroup was named as WALSHES.
The final result of all this is that the Windows 10 laptop CANNOT see a NAS device if the workgroup is called WALSH, but the laptop can see the NAS device if the workgroup name is set to WALSH01, or WALSHES on both devices.
If I swap from the workgroup name WALSH01 back to WALSH, the devices do NOT appear under Network (neighbourhood).
I suppose I could generalise and assume that workgroup names of 5 characters DO NOT work reliably for WINDOWS 10, but workgroup names of 7 characters (or more) DO work reliably. I’ll leave that for others to experiment with