SATO CT4-LX Operator's Manual page 483

Error Message 1024 (Head Density Changed)
When there is an error with the product, the error message appears on the screen.
Tap the error number button to show the details screen.
Check the cause and countermeasure, and then take appropriate action.
To clear the error:
Check the message that appeared on the screen.
Cause and Countermeasure
Cause (1)
The print head is not installed.
Countermeasure (1)
Install the print head.
Cause (2)
A new print head with a different resolution
has been installed.
Countermeasure (2)
Install a print head with the same resolution
as the old print head.
Contact your SATO technical support if the error cannot be resolved.
Contact Information for When You Are in Trouble
Reference
Replacing the Print Head
Replacing the Print Head
483