Are they also on latest version of Windows? If not, also do that. Yes, Windows has bugs. And yes, Microsoft fixes bugs in Windows. But you actually have to update to get those fixes.
Arbitrarily staying back on Windows XP, 7, 8, or 10, is just silly internet nonsense that only benefits hackers.
So, update to Windows 11 (it's free), and apply all security & features updates.
If, after doing that, they still get errors, then the problem is they have faulty network adapters. Cheap chinese adapters, or incorrect drivers installed. Or both.
You can confirm this by running
Get-WMIObject -Class "Win32_NetworkAdapter" | Format-List * in PowerShell and see if all the real adapters are correctly reported as a “physical adapter” and if they have an associated MAC address. If not, you know which adapter either has a broken driver install and/or the adapter itself is broken.
Long story short: if they actually apply all updates to Windows and actually update their drivers, and the hardware is functioning, then everything will work fine.