Try checking the physical connection. If there is a successful connection the LEDs on both sides of the cable should be blinking.
Execute the following commands on the machine, where you have problems with.
And then search for your network adapter, e.g., Ethernet. This will provide you with your current MAC, IP, DNS and Gateway.
This tests whether the general connection to the internet (and your DNS)
This checks whether your DNS is set up correctly.
Just a little different commands