Bino's
How have you set the print buffer?
Click on Start, then Printers & Faxes. check that you have the "problem" printer set as default (black circle with tick inside against it).
Right click on that printer, choose Properties and then the Advanced tab.
What settings do you have in there?
Is the printer connected directly to the PC or via a print server? If connected to the PC, is that via USB, serial or parallel port? (sorry if you've already given that info earlier).
Not sure if I can do anything with the info you give on the above, but there may be a clue in there somewhere.
Cheers
ST