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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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Since HTML documents are printing correctly, it is possible that the large black ink tank in the unit may be clogged. You can print a nozzle check pattern from the printer to see if the inkjet nozzles are dispensing the ink correctly. To do this, please follow the steps located here. Once it is printed, please examine it and compare it to a correctly print pattern here. If all of the colors are not appearing, including the black grid at the top above the colors, performing print head cleanings on the unit may resolve the issue. To perform the cleanings, please follow the steps located here. We recommend performing at least one cleaning and two deep cleanings.
Should you still experience difficulty, the printer may require servicing; please call or email us using one of the methods on the Contact Us page for further assistance.