Logon difficulties today in Lab C exposed a problem with the way DHCP addresses are assigned and released by the DHCP server. IP addresses are being released 24 hours after a machine is shut down, and as a result, we had about 1/3 of the machines in Lab C fail to pick up an IP. I had the DHCP service set to release 5 minutes after a machine is shut down so this should not be a problem in the future.