My 7740 prints all colors as black, even test page

[JRJ_IN_YYC]

My Officejet Pro 7740 has stopped printing in color.

There are no error messages and the cartridges are new. When I print from Windows Paint all colors are black -even yellow is black - not gray.

When I print the print quality test page with a color photo, it prints a perfect grayscale, as opposed to a color photo missing c,m,y. Similarly a color copy. The printer test page with ABC  at the top and 6 graduated color rectangles show as  3 shades of gray each.

It is as if the printer is not trying to print color as opposed to out of color ink.

The last time it printed color was perfect, no ink issues. Since the copy and test pages won't print color, it mustn't be a Windows/Driver/Settings issue.

[Betty0610]

@JRJ_IN_YYC

Welcome to the HP Support Community.

Yes, this is hardware related.

Do you've another set of color inks with you?

Give us some reinforcement by clicking the Accepted Solution button, that'll help us and others see that we've got the answers and did reply to you!

Thanks!

Have a great day!

[JRJ_IN_YYC]

I had already replaced the cartridges with a new set before making my post. Old and new act the same.

I  also removed, cleaned and re-seated the printhead.