Q. Why is it that I cannot remove a subnet from the Info window? When I select the subnet and click 'Remove' and confirm 'Remove Subnet' in the displayed message, the subnet remains in the list?

A. It sounds like you are trying to remove a subnet that has been discovered by SNMP. You can really only remove those subnets that you have added manually. It will "remove" those found by SNMP, but it will immediately rescan. If the subnet is rediscovered, then it will be reentered in the list.