RandyBob,
You have to set up the PC with the USB printer for sharing. See below:
Share and Share Alike
After I installed my new printer on the computer, I wanted to use it from other computers. I even wanted to print from my laptop computer, sitting on the patio, connecting to the network with a wireless NIC. Before I could do that, I had to share the printer. Windows XP doesn't automatically share printers, which is a good thing when you don't want to share your toys.
To share the printer, I opened the Printers and Faxes folder on the computer that was connected to my printer.
To open the Printers and Faxes folder
? Click Start and then click Control Panel.
? Click Printers and Other Hardware, and then click Printers and Faxes.
? In the Printers and Faxes folder, I clicked the printer's icon and, in the tasks pane, I clicked Share This Printer.
? I opened the printer's Properties dialog box, and clicked on the Sharing tab.
? I clicked Share Name, and then clicked OK.
That's it?the printer was immediately available for other computers to use.
Now that I had a network printer, I was ready to connect to it and print from other computers on the network.
To connect to the printer
? I opened Control Panel, and clicked Printers and Other Hardware.
? I clicked Add a Printer.
? Instead of adding a local printer, though, I clicked Printer Connection and then browsed the network for the printer.
The whole process took less than a minute before I was printing to the network printer as though it was connected to the computer.
Check the silly stuff. Printer is on and PC connected to printer are on. Have you checked network connectivity between the PCs? Pinging each PC?
One last comment. I have a Netgear Router and two computers and one printer. I bought a Netgear Print Server Device so I could share the USB printer without having to directly connect the printer to a PC or have the connected PC turned on. The USB printer becomes an addresseable device on the network meaning I can see the printer as a connected device. I print directly to the print server which spools jobs and sends the job to the printer over the network.