Try printing from another PC.
As to details you didn't reveal what App, web page or such so no one can guess that a print background or watermark is enabled or not.
I am getting a shaded background on my paper, when I print it out from a Dell 3110cn Color Laser Printer.
What can be causing this? Is someone receiving a copy of my document, as to why it is printing out with a shaded background?

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