Open the Windows 7 "Control Panel." An icon for this folder is in the "Start" menu.
Open "Network and Sharing Center." Choose the option reading "Change advanced sharing settings." Select "Turn on file and printer sharing." Click "Save Changes." This gives your computer permission to share printers and other content over a network. Close "Network and Sharing Center."
Return to the window labeled "Control Panel." Open "Devices and Printers." Find the icon for the USB printer that is connected to your computer, and select it using the right button on your mouse. Click "Properties."
Click "Sharing." Check "Share this Printer." Click "Apply." The USB printer is now a network printer.