Carlos has recently updated to Windows 10, but whenever he plugs his computer into ethernet cable, it disconnects and defaults to Wi-Fi. Leo says that in network settings he can prioritize his connections. So he should just make sure his ethernet connection has a higher priority than his wireless connection. He can also just turn off wireless. Another thing that can cause problems is IPV6 compatibility, so he should turn that off as well.
To prioritize ethernet over wireless in Windows 10, open the Network and Sharing center. Then select "Change adapter settings." Go to the "Advanced" menu, and choose "Advanced settings." Now you'll see the "Adapters and Bindings" dialog that shows the order of prioritization for network services. Click on ethernet, and click the arrow to make it the first in that list.