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To have a better understanding of your issue, please let everyone know what operating system (Windows Vista/7/8 or Mac OS 10.X) you are using. That way, the community will be able to assist you with suggestions appropriate for your product.
Any other details you'd like to give will only help the Community better understand your issue!
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Check to make sure that your computer is connected to the same Wi-Fi network as the printer.
Also, try power cycling the printer and restarting your computer to see if this helps.
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