While googling I came across someone else with the same problem and the suggestion was that the heads had dried out and to soak the heads for an hour in a quarter inch of water.
I did this and the water turned blue, aha I thought the cyan is now unblocked, so off I tripped to the printer and I could see cyan and pink on the heads. Did a clean cycle but alas no cyan was printed again just magenta and no yellow.
So I have ordered some remanufactured ink cartridges to see if it is the cartirdges (3 off) that have dried out or the printer connections to the cartridge itself.
I have now semi-retired it to the study for black printing, yes the black cartidge is fine, and pinched the D1460 for my studio for colour printing. Also trying the 710c on Windows 10 x64 the driver doesn't work at all so I have sent feedback for that. I cant imagine MS fixing a driver for such an old parallel printer but you never know.
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