How to Change a Printer Passwordby Stephen Lilley
If you've password protected your printer, this password was added via the computer to which the printer is physically connected. That machine is where the printer's settings file originates. Before any networked computers can use the printer, they will need to enter the password. If you want to change the password on your printer, you will have to do so from that original computer.
Click "Control Panel."
Open "Devices and Printers."
Right-click your printer's icon.
Click "Properties." In this window, choose "Sharing." Use your keyboard to specify a new password for your shared printer in the password box on screen. Click "Apply" to change your printer's password.