How can I achieve this:
1. step: I would like to get the Ethernet ("RJ45") MAC Address,
2. step: if there is no existing one, get the WiFi's MAC Address
Important:
Thanks
There is the NetworkInterface.GetAllNetworkInterfaces() to list all network adapters. You can then use the NetworkInterfaceType and/or name and description to filter and order adapters. Use .GetPhysicalAddress()
to get the MAC address.
If this is for a license system I would suggest listing all valid adapters for whoever grants the license to chose from. A network adapter may be movable between systems, and that may or may not be desirable.