Select the Addresses tab.
Select the IP address's network.
Select one or more IP addresses you want to delete.
If you want to delete more than one address, press the Control key while you click with the mouse to select multiple addresses. You can also press the Shift key while you click to select a block of addresses.
Choose Delete from the Edit menu.
The Delete Address dialog box lists the address you selected so you can confirm the deletion.
If you want to delete the host names from the hosts table, select Delete From Hosts Table.
If the host names were generated by DHCP Manager, you might want to delete the names from the hosts table.