Win2003 DHCP: Loosing Scopes

I have one primary dhcp server for multipul subnets. After bringing on new
subnets (6 new subnets total, and about 35 all together) the new subnets seem
to disappear. At first just the address pool would dissapear (along with the
router), once with the entire scope disappearing.

After the updates that microsoft pushed this last tuesday, upon reboot we
lost all of these new subnets (all the others still intact).

Any ideas on why these scopes disappear? They're configured exactly the same
as the older ones.

Thanks!
Thomas Lasswell