I've just installed Zen 7 SP1 on the second server on our network.
According to the installation screens and the basic log, the install was

Now, I can boot a workstation using PXE. PXE boot was working before
the upgrade.

At first PDHCP was not loaded, so I unload DHCPSRVR, loaded PDHCP, and
reloaded DHCPSRVR. Also, the ZFDSTART.NCF was not in the autoexec.ncf.
I now have ZFDSTART before the DHCPSRVR loads.

DHCP is working from the server. I haven't verfied my PDHCP.INI file or
OPTION 60 yet.

Anyone have any other ideas? The first server upgraded to Zen 7 SP1 has
PXE working.