Thanks for the reply, but I read the instructions and that was not the problem. If you are trying to do this, and having problems, here is THE SOLUTION (at least for me it was) and I hope this spares someone from my headache:
FIRST - DISABLE ALL of HP's Useless, meaningless warnings, etc. under "Tools" > "Alert Settings" at the top of the HP Utility Tab.
If you're trying to profile from 13x19, that probably does it. IF you are trying to profile from a previously printed target, as I was to save the few sheets of this crappy Ilford Gold Silk I bought, and the profiling process keeps cancelling, what is PROBABLY the issue is this:
-----On the z3100 Main Menu on the Printer itself, go to "Setup" > "Printing Preferences" > "Paper Options" > "Sheet Load, Check Skew" > make sure the "YES" box is CHECKED. If the "No" box is checked and you have been happily bypassing the skew check as I had been, profiling from a pre-printed target AIN'T GONNA WORK.-----
I didn't find this anywhere, I eventually figured this out. Read my posts today and you can see what fun I've had!
After all that, I profiled the Ilford Fiber Gold Silk and why anyone would print on this stuff is beyond me. I profiled with Gloss Enhancer ON and even with that profile, and Ilford's canned profile, the gloss differential and bronzing is ridiculously bad. Maybe once you're print is framed and hanging on the wall you're OK, but don't let anybody flex this paper in the light...I can't believe how bad this stuff is. Even HP ID Satin blows it away. If someone printing on a z3100 has achieved zero bronzing and zero gloss differential on IGFS, please let me know how you did it. Right now I wouldn't pay 2 bucks for a roll of this stuff, much less the exorbitant price they charge. Looks pretty good, until you change angle in the light. Then it's a turd. I'm printing a client's color files. Maybe B&W is better? HP ID Satin looks 100x better for what I'm printing.
After updating firmware, I also had problems with connecting the z3100 via Ethernet. Sometimes it would show, sometimes it wouldn't. Rebooting computer and the z is time-consuming and gets old fast. Highly recommend connecting your printer via USB. Never had a problem in the last couple of years using it that way. A few hours with Ethernet after the update, and nothing but connectivity problems.