Eric!
Maybe you have the same fault with your printer as I have with my two year old HP Photosmart B9180 printer, conected to a Power Mac G5.
It all started when I was printing from Lightroom 1.3.1, the paper was ejected when the printer still was printing. I tried to print from Photoshop CS3, but the same thing happen there.
So I tried with some other pictures with had print fine some days before. Landscape pictures did print ok, but when I tried with portrait I got a message in the printers control panel saying that size of the picture didn’t fit on the paper and the printer refused to print.
And now I don’t even get that message, the printer lockup with the error code 00C78475 - for which I cant find any explanation.
The system console log says: Adobe Photoshop CS3[346] InkChecker could not launch, launch path not accessible.
It is possible to print from other applications than Adobes, the preview application prints fine.
And its no differents between USB and Eterneth connections.
The only thing I can imaging that can cause all this, are the upgrade of the OS to the last version 10.4.11 I made last Friday. I think - but is not 100% sure that all this has happened after that point.
Not shure what to do from now.