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I presume the error code 0x91 is appearing on the printer itself.
Try turning the printer Off, clearing any paper that may be jammed in it, and leaving it Off for at least 10 minutes.
Also try removing one cartridge, seating it into its place again, then removing the next cartridge, seating it in its place again, and so forth for all the ink cartridges.
(Avoid touching the copper-colored contacts, or the inky underside, of the all and any cartridges... that may ruin them.)