ZFD HP5, also saw in HP4, maybe HP3

Dell GX620 (so far anyway)

I'm at the point of starting to image some systems that were last
successfully imaged last year.

I've got a handful of systems that won't enter the PXE imaging system either
manually or via an auto-image.

Normal PXE boot, gets IP and knows where the imaging server, etc. is.

At the point where I should be able to enter the manual image menu (holding
down ctrl-alt) and/or start an auto-image, it doesn't and the system exits
PXE and boots the current OS.

It's not the keyboard, or BIOS version, etc. The system is imported and can
be remote controlled, it also gets the correct application associations.

The only solution is to clear the ZIS info on the disk either by booting
from a ZEN bootcd or via ZISWIN (if the system still has an OS).

Once the ZIS info is cleared, and the system boots again, the ZIS info is
re-populated and the system will now enter manual imaging and/or take an
auto image. After that, there is no longer a problem.

So the question is, what in the ZIS information stored on the PC would keep
it from allowing me to enter manual imaging via PXE. Obviously, I've got a
workaround fix, but I'd sure like to know what's causing the issue.