I work in a student computer lab where large files, such as unflattened Photoshop and Illustrator files (Creative Suite 3), are sent to the printer fairly often. Were having big issues with the machine hanging, spooling up for long periods of time, or even spitting out trash, especially after two or more of these jobs has been sent. An unflattened PSD file might hang for over an hour before getting around to printing. Even a flattened or condensed file hangs longer than it should, especially if printed several times. Then normal files coming afterwards have trouble printing. We often get here an error message that says No %%Bounding Box: comment in header!" Restarting the printer always seems to clear out the congestion and start the process over, though. We think it might be related to the postscript file, or PPD file, that comes with the HP drivers. Were working on OSX 10.5 (Leopard, not Snow Leopard) which may or may not be an issue, and our printer drivers are upgraded to the latest version, which is 18.104.22.1681. Our PPD file is version 4.3.1.094, which seems to be the latest file version this update will install. We arent going to be upgrading the labs to Snow Leopard any time soon, so thats not an option. Any ideas on what the problem is, or how we can fix it?