Even though there are no duplicate IP Addresses, some IP Addresses assigned to Windows XP DHCP clients are marked as BAD_ADDRESS in the DHCP server address lease table.
This behavior may occur if you performed a procedure similar to:
1. You disconnected the network cable from a computer that is turned on.
2. You change the TCP/IP Properties to set the IP Address of the network adapter to a static IP Address.
3. You connect the network cable and verify connectivity.
4. You disconnect the network cable.
5. You set the TCP/IP Properties back to Obtain an IP address automatically.
6. You connect the network cable.
This behavior will occur if the DHCP client sends incorrect DHCP decline information after you change from a static IP Address back to a DHCP address.
NOTE: If you release the static IP Address before you disconnect the cable, or you restart the computer, this behavior will NOT occur.