This PC is 6-7 years old with Intel processor and board. The networking is slightly complicated and I suspect Mageia is getting confused by that. The onboard Ethernet has been disabled in BIOS (it still works, though), with an Intel PCI card doing the Ethernet duties. There is also a Linksys Broadcom-based wireless PCI card.
I just built a new Cinnamon system and updated until there were no more updates to be had. I looked at the default networking icons. The world one had a green checkmark next to it, but the other one had an X next to it. I removed the X-ed one, but a replacement immediately appeared, the one with two PCs, but it has a red X next to it. The tooltip on it is "Networking disabled." I am using the system to write this message, so the networking is definitely not disabled. When I look at the tooltip for the world icon, I see "Networking is up on interface Wired (Ethernet)," followed by the usual IP addresses. The system is connected to the Internet via Ethernet.
I have used a few other Linux distributions on this PC, most recently Linux Mint, as well as Windows 7 and 8.1, and they were never confused by networking.
When I right-mouse-click on the two-PCs icon, I do not see a Remove option, so I'm not sure how to remove it from the screen. As a test, I deselected "Enable notifications," but the red X remained.
Any hints?