Start>Control Panel>Printers and Faxes
Right-click your printer, check status... Does it show "Use printer Offline" or "Use Printer Online?"
If it shows "Use Printer Online" then click that and see if the printer takes off printing. It also helps if the printer is selected for "Online" at the printer... if it has that feature... and most of all... the printer must be plugged in and connected to the computer.