Hello Victor97,
It sounds like you have our imageCLASS MF4770n (the model number appears near your LCD screen on your printer) and you are sharing the printer. Printer sharing is when you directly connect the printer to one computer with a USB cable, this computer acts as the host and will allow other computers that are connected to your home network to print.
Did you try restoring the defaults on the 'main computer' (see steps below)?
1. Select the 'Start' button from the bottom left of the Windows screen, 'Devices and Printers'.
2. Right click on the MF4700 Series UFRII LT icon, and then select Printer Preferences from the menu that appears.
3. In the Printer Preferences window, click on 'Restore Defaults' toward the bottom of the Basic tab, then click Apply and OK.
If you have already completed the steps above and the issue persists, what size paper is loaded in your MF4770n and what is the paper size selected on your printer?
To check the paper size on your printer, please follow these steps:
] or [ 
] (Paper Settings).
] or [ 
] to highlight <Drawer 1>, and then press [OK].
] or [ ] (Paper Settings) to close the <Paper Settings> screen.
If you need immediate assistance and you're in the USA, please click http://Canon.us/ContactCF for our US-based support. If you're outside of the US, please click http://Canon.us/4xf7 for support options.
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