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That error message signifies some sort of printhead motion or carriage motion fault. The carriage is not moving properly, or the printhead has a problem. Or the machine's workings are simply not in order vaguely in reference to carriage and printhead.
Open the printer, and see whether the carriage moves into place in the middle of its range. If it does not, there is confirmedly a problem with the carriage motion and sensing of carriage motion and position.
Look for loose parts within the machine, or paper that might be jamming in the works, or anything of that sort.
Also inspect as to whether the 'encoder strip' might be dirty or have dirt or dust clinging to it. If it does, then it may need to be cleaned (if so I will give you instructions as to how to go about cleaning it.)
The 'encoder strip' is located where the red outline shows it in this picture:
Let me know what you observe and find upon inspection, and whether the printhead/carriage assembly moves, or is staying in place when you open the top cover, and I will instruct you further as to what to do.