DHCP Scoping Problam!

Hi group,

Recently, I tried to increase the range of DHCP server in the scope property. I don’t know why somehow it doesn’t allow my to, because it said, “The range is extended less than the specified backward extension. Extend the range in integral of 32 addresses.”
I tried different ranges, but still received the same message. Is there something else I need to configure first in order to do so? Would you mind to tell me what should I do to solve this problem?

Regards,

-Mak