My pc only recognizes my WD TV Live Hub when i'm on Wifi

Here is the problem: When in my pc i’m connected to via ethernet, it can’t find the device, then I turn on the wifi, and the WD TV appears, why is this happening?, also, my WD TV Live Hub is connected via Wifi.

Thank you, and sorry for my English

Check your WiFi router.   Many have a feature called WiFi isolation that does exactly what you describe.

Thank you for your answer, I don’t seem to find the wifi isolation thing in my router webpage.

Other thing that happens is that is I change the connection to ethernet, it also works, but if I restart the computer it stops working.