There is one remaining test that you could try to regain full-line function.
Go into the Properties settings for the printer. Carefully comb through all the settings, and turn Off all
'advanced'-type functions. I can't list them since they may differ for each manufacturer and model. Also experiment with the Port settings if you can. You may have to test with multiple combinations of settings. If this fails then a new cartridge is warranted.
Does the printer still fail if the document is double-spaced - a blank line between each printed line? (You can't operate this way, but it could be interesting to test.)
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