Computer Disappears From School Network - Cannot Reconnect To Printer

win xp I work at a junior high school. A lot of the computers are part of a work group so they can share printers.

I'm having problems connecting to a printer. It has worked for a long time, it's still my default printer, but when I try to access it, it gives me a spooling error.

Now here's why I think it's a network problem.I can't access the main computer's network location (the one hooked up directly to the printer). All the other computers come up on the networkjust fine. And the one in question is only able to access very few computers in the network browser. let me simplify:

computer A/ brother printershared computer B/no longer sees A on network A/ sees only a small portion of other computers on network B/ sees all computers but A

Again, I don't think it's a spooler problem. It probably gives that error because it's a default printer with a lost connection.