I am trying to change my Fios-G1100 router's DHCP server to give out class a ipv4 addresses as opposed to the regular 192.168.1.x ones, so I changed the settings under My Network->Network Connections->Network (Home/Office)->Settings to look like this:


The problem is when I click apply, I get the following message:
"The number of IPv4 Addresses in the DHCP IPv4 address range must not be more than 256."
Is there some other setting I must change to have a wider class a ipv4 address range?