MAC already exists

[zdcyclops]

I sold a matricom G Box Q to a friend, last night I picked it up at his house to get it to connect to the server, I hit the reset button and saw that the MAC was a spoofed one I had used on my Windows box just one character different. I changed it to the MAC on the Android box and found it was already in use. Am I sol ? I can install a spoofer change the MAC but it will only last until the box is shut off. My friend is brain dead when it comes to PC's. What happens if you by a box for this and it's MAC is already in use?

[Marley]

no mac should be good when you change it