Why would an IP address not release from an old computer after it was taken down and off the network?
Let me explain what happened... I set up static IPs for all of my computers and when replacing an old computer, give the new one the old IP. So computer "A" was assigned 192.168.1.150
This computer had to be replaced, so it was shut down, taken completely off the network and put to the side.
Computer "B" is then brought up onto the network, assigned the IP 192.168.1.150 but was reporting that there was an IP conflict. So the computer kept dropping from the network and nothing would work properly until I changed the IP address.
I then gave the new computer about 12 hours until I changed the computer back to the old IP again (for testing sake) but still reported IP conflict.