OK, so I have encountered a problem with my Z3100 post-upgrade to the latest firmware and drivers for Vista 64. This is a vanilla 24" Z3100, and the problem doesn't appear to have anything to do with the OS, however.
I noticed that the HP Printer Utility icon in the system tray was showing a red exclamation (!) warning, and so I opened the utility to see two warnings: The Gloss Enhancer cartridge was empty (I knew that was coming, no surprise there) but also a second warning that no paper was currently loaded. Now that was unexpected as I had loaded the printer just a couple of days ago with a 100' roll of Red River Polar Satin, and had printed about 50 9x12's with no problem.
I replaced the GE cartridge and the printer reset, clearing that warning, however the paper warning was still in effect. I unloaded the paper, then tried to reload it. First, it was difficult to get the printer to take in the paper from the back, like it just wouldn't grab hold of the paper. Finally, I was able to get it to grab, but it just started to perform the following over and over again: feed the paper forward about 4 inches, head moves from the right to detect the paper and apparently doesn't detect the paper, then starts again. If I were to let it continue, I think it would feed through the whole role. I turned off the printer and tried the load procedure a couple of times but still the same behavior. I even tried changing the paper type from "custom" to HP Pro Satin, but still no luck.
I am thinking that this may be a ssue with the new version 6 firmware release. I have seen at least one other reference to paper loading issues, so I thought that I would start a new thread on this. Has anyone experienced a similar problem? I will be calling HP in the morning, so I will update this after that call.