IP address problems
My MacBook says my IP address is already being used. I followed the directions I found here to get a new IP. But after I click "renew DHCP lease" button, it asks me for the client ID, what do I do?
MacBook Air, iOS 9.1
Restart your router
This issue is generally caused by the DHCP host, which is your router, and not the DHCP client which is your computer. Restarting the router should almost always resolve the issue.
The Client ID would be the network adapter's MAC address.