Lexmark C750 User Reference Manual page 104

1565 Emul Error
Load Emul Option
What this message means:
The download emulator version on the firmware card does not match the printer code version.
This error can occur if you update printer firmware or move a firmware card from one printer to
another.
What you can do:
The printer automatically clears the message in 30 seconds, and then disables the download
emulator on the firmware card.
Download the correct download emulator version from Lexmark's Web site.
2<xx> Paper Jam
What this message means:
The printer detects a paper jam.
What you can do:
Clear the paper path.
See also:
Clearing the paper path
30 ITU Missing
What this message means:
The image transfer unit (ITU) is not installed or is installed incorrectly.
What you can do:
Turn the printer off, correctly install the image transfer unit, and then turn the printer on.
See also:
Replace the image transfer unit and transfer roller
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