LPR Printing Keeps Crashing

At our school we have our printers shared using LPR ports. We have two omputers in particular that are setup to print to the other computer using LPR ports. For some unknown reason, the computer that the printer is attached to prints fine whereas the computer that has to port the information doesn't work with an error "Printer Busy or Error". If we swap the printers around, it works fine for about 10 mins before the problem swaps computers, if we swap it back, the same thing happens. We have reinstalled Windows XP many times but it didn't solve the problem.

Can anyone please suggest why this may be happening, how to fix it or a better way of achieving this task. We don't use shared printers for the reason that they sit in the users profile and not locally, we need them local.