This was a problem but I solved it and thought I would pass on the info incase others had the same trouble - hope this is ok in this forum.
My HP DeskJet 890C was printing fine until the carriage suddenly locked up. I would switch off and manually move the cartridge cradle back to the docking position then switch back on. It might do this a number of times and then work ok for a couple of sheets then lock up again.
I tried new cartridges but problem persisted and I was on the verge of throwing it through the window. As a last resort I disconnected from PC and mains and removed the case. Then I cleaned the small amount of gunge off the track and sliders and lubricated with WD40. I refitted the case and reconnected. That was about 6 months ago and several hundred sheets ago and the printer is working flawlessly.
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