-steve is right ... it's the buffer
question is why it's not clearing
error printing often makes them stick .... it just happens ...
there is however another possble
go to the properties page for your printe (probably the sdvanced tab) take the tick out of keep printed documents
also try disabling spooling (you can always put it back)
but big print queues realy need a print server to supervise them (your router may have one that just needs enabling)
finally try printing RAW
don't forget to restore any options that don't make a difference