Error: BOOTP from dynamic client and no dynamic leases

[Melissa Young]

Hello,
This DHCP/DDNS server was working, so the
configuration should be fine. After putting offline
for a couple of weeks, now it keeps getting errors
like this:
 
BOOTREQUEST from 00:20:49:48:7a:18 via dmfe0: BOOTP
from dynamic client and no dynamic leases
 
This "00:20:49:48:7a:18" is the MAC address of the
router connecting to the DHCP server. DHCP service is
not working and every client update is denied.

Please help. Thanks a lot in advance!
 
Melissa Young,
System Admin