I found the answer to those who have similar problems with using an HP DeskJet 722C connected to an XP computer & trying to print from a Windows 7 Laptop. I found the answer on HP Forums. Basically there is a patch that needs to be installed. You set up the port & then install the driver
for the HP DeskJet 720C. Then go to the link provided & download the 3 files. Put them where they tell you to even overwriting what might be there already. Then by magic it works.
Here is the magic link to the HP Forums. Read the message click the link & follow the directions. Problem using networked Deskjet 722C from Windows 7 - HP Support Forum