You need a dhcp server on your PC.
If Alt-F can't find a DHCP server (which usually is your router), it will assign itself the IP 192.168.1.254. If your PC IP is not in the 192.168.1.xx range, it can't communicate with the box.
So you have two hipotesys:
1-turn on or activate a DHCP server on you PC, then reboot the box
2-assign you computer a static IP in the 192.168.1.xx network (say, 192.168.1.100)
But you don't supply enough info. How is your PC connected to the internet? Does your PC has two network cards? Why isn't the box connected to your local network? What is your PC operating system? What firmware was you running on the box before? etc,etc,etc. You have to give context and history to your help request, otherwise is liking phoning your medical doctor and telling him: "I don't feel good, help me."