Linkstations suddenly inaccessible

[gavinoddy]

I have two (admittedly old) Linkstations on my network: an LS-VL and an LS-CHL-V2. I use them for PC backup and for long-term storage of stuff I don't want cluttering up my PC drives. Suddenly they have vanished. Mapped drives don't connect and NAS Navigator 2 doesn't see them. However, if I enter their IP addresses into a browser there's no problem accessing the web interface and logging in directly over the network, so they're both up and running with live network connections. All was fine until a couple of weeks ago, when I started getting file history / drive reconnection failure notifications from Windows. I haven't changed the configuration of the NAS or any network kit so I'm guessing that something's changed on Windows: I'm running a mix of Windows 10 Pro and Windows 10 Home, all 22H2.
I've tried a few things suggested on general forums without success so I thought I'd see if anyone here has any suggestions...
Gavin.

[davo]

SMB1 which these older units use is no longer supported on Windows 10 and 11. You can enable it on the OS but it's a major security risk.

[gavinoddy]

Thanks, davo. I'd already investigated that, and the settings on the PCs hadn't changed.

It turned out to be something completely unexpected. One of my PCs lost network connection. Another PC connected to the same switch was fine, but both the Linkstations are connected to that switch too which made me suspicious. It turned out that the switch was failing in a bizarre way: some ports were working fine but what protocols were and weren't working with the others depended on the port. I replaced the switch and everything started working.
In the meantime I've purchased a new NAS server so I'll gradually migrate operational network storage onto that, leaving the Linkstations for extra redundancy and long term storage.

I'm aware that SMB1 has security failings but presumably someone would need to have have direct access to my LAN for this to be a risk?