regularly spaced horizontal lines on paper with either cartridge

[hillyandj]

this is a HP Envy 7800 all in one printer which was printing fine but now it has a white or lighter print line every 28 mm across the page whether printing in color or black. I am using the instant ink cartridges and did recently replace the color one. 

My husband thinks it may have to do with the rollers but I cannot see how to do anything with them

[Betty0610]

@hillyandj

.Welcome to the HP Support Community.

Does this happen on copies too?

Try the steps from here: https://support.hp.com/ro-en/product/model/9073160/document/c05541385

Let me know if this helps.

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