I don't know what you're printing, I've encountered this situation before, the pin printer printing vouchers, vouchers, vouchers are half the height of the A4 paper, but choose to print the selected A4 paper, then there is a print one empty one of the situation.
If you need to reset the paper can be (XP system can be set up in the following way) Control Panel - - "Printers and Faxes -" right-click in the blank space and select Server Properties - "New Paper, to create a new paper size in line with your actual situation, and then print the time you can choose from the printer's paper type.