Event ID 1053: conflict with Firewall

This morning, seemingly out of the blue, I received an error message from my server that the DHCP service had stopped.
Event ID 1053
Supposedly, the Firewall (Firebox X Edge) has established itself as the DHCP server. Any ideas? I’m about to have a look about the firewall site and see if somebody has tinkered with something. It’s been trouble ever since the network was rebuilt.
Thanks,
A.