PXE boot problem

The workstation does a PXE boot, receives DHCP addresses, does a Auto-select
Zenworks Boot, loads Zenworks Network Mangement and Security Preworx and
displays all correct IP addresses. At this point, the load stalls with this
error: Action Local Boot - Zenworks Shutting down
Running nw 6.5 sp6 with zen 7.1 hotpatch 5 applied just this morning. This
was happening before I applied the hotpatch, I applied the hp5 just to see
if it would help. That didn't work.
I can't really tell you when it did start happening because I just got back
from vacation and one of our staff told me today that they couldn't image
and haven't been able to for a while. But they are not sure when it stopped
working.
Anyone able to give me an idea where to start?

Teresa