Remove the Toner Cartridge and Imaging Unit.
Thoroughly shake the Imaging Unit.
Re-seat both supplies back into the printer.
Important third-party supplies check!
Genuine supplies - Confirm the use of Lexmark - branded supplies, toner cartridge, and imaging unit. Third-party supplies may not be compatible with the printer.Refilled or reworked supplies - Confirm that this toner cartridge or imaging unit has not been refilled or reworked. A refilled toner cartridge can trigger this error.
If Third-party supplies are installed or Lexmark toner cartridge / imaging unit has been refilled or reworked, then make sure to use a genuine and original Lexmark supply item. Should this correct the issue, please contact the sales vendor for a refund or another replacement of the supply that was causing the issue.