Black pages are typically caused by a contact issue that is preventing the drum in the toner cartridge from being grounded properly. Remove cartridge, check for any foreign material or bent contacts (usually made of wire about the size of paper clip metal). Re-insert cartridge and try again.
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Thanks for the quick answer !! - Tried your suggestions but without success.
I wish I could find a real HP Support - I mean a real person in a Chat - even the phone number of the german support doesn´t work. I´m spending days now to get this machine working . Nothing to recommend !!!
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