In response to what knuttle wrote :

Is there a SIMPLE piece of software that will allow me to tell what
devices are using my local area network.

I don't know the answer, but it is a good question, worth the combined
effort of the group to arrive at a better answer, where let's hope someone
_already_ uses a good free network scanner they can recommend for us.

On Android, I have a ton of network tools, some of which "might" have
Windows equivalents...
https://i.postimg.cc/mrZdzpXs/network02.jpg

Looking at Android and seeing if any of those apps are on Windows, I found:
o Fing
https://www.fing.com/products
o Metageek inSSIDer
https://www.metageek.com/products/inssider/
o Nmap
https://nmap.org/
etc.

Personally, I don't need this information on Windows, but my router will
tell me that information. Looking now, I see my router provides a table
organized by wired & then not wired, and then by MAC address & IP Address,
both of which are incomplete tables.

Of course, MAC addresses have a first half that tells you the manufacturer
if you're lucky, but overall, I find that information less helpful than you
would likely want it to be.

Googling a bit, there's also
o WiFiHistoryView by Nirsoft
https://www.nirsoft.net/utils/wifi_information_view.html
o NetSurveyor
http://nutsaboutnets.com/archives/netsurveyor-wifi-scanner/
o ZenMap
https://nmap.org/zenmap/
o NetCrunch
https://www.adremsoft.com/netcrunch.tools/
o Angry IP Scanner
https://angryip.org/
o Simple IP Config
https://github.com/KurtisLiggett/Simple-IP-Config
o HoverDesk
http://www.hoverdesk.net/
o sn0int
https://github.com/kpcyrd/sn0int
o Masscan
https://github.com/robertdavidgraham/masscan
o eToolz
https://www.gaijin.at/en/software/etoolz
o WakeMeOnLan from NirSoft
https://www.nirsoft.net/utils/wake_on_lan.html
o IP Address Tracker
https://www.solarwinds.com/free-tools/ip-address-tracker
o WinMTR
https://sourceforge.net/projects/winmtr/
o Advanced Port Scanner
https://www.advanced-port-scanner.com/
o DipIPsoft
https://www.dipisoft.com/articles.php?lng=fr&pg=2116&mnuid=2211&tconfig=0
o Cisco FindIT Network Discovery Utility
https://www.cisco.com/c/en/us/support/cloud-systems-management/findit-network-discovery-utility/model.html
o SoftPerfect Network Scanner
https://www.softperfect.com/products/networkscanner/
o Advanced IP Scanner
https://www.advanced-ip-scanner.com/

And lots more at:
https://alternativeto.net/software/fing/?platform=windows

Maybe one of those will be used by the cc list who can advise us?
--
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