Lexmark C3326
121.71A error code at first boot up or while printing or doing a calibration
Turn the printer Off and turn it back On after a minute.
Check the printer if the error message still appears.
If the issue does appear, please contact Lexmark support for further diagnosis of this issue.
An “Invalid Engine Code” error message indicates a problem with one of the internal operating programs of the printer. The printer is not able to receive, and process print jobs until the printer is reset.
Does a 900 error message appear on your printer? Check out the following steps to troubleshoot the problem.