Same problem. I went through HP help and replaced the ADF cartridge and reset it, but still printing a black line. Only does it when sending faxes or making copies. Does not do it when printing from computer or receiving faxes.
Had the same problem. Fixed it, temporarily, when I opened the scanner and cleaned out the gunk that had melted in the recesses on the scanner bar - thing that goes back and forth. It worked for awhile, but came back about 100 scan pages later. HP claims that they do not have a replacement part.
I am having this problem ,,,,not the cartridge, tried a new one
Is this happening when you print or when you scan? If when scaning you could have something on the scanner bed... If this is happening when you print, it could be the cartride is defective.
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