BJTZ228 Invalid length. Form length metric can only be Inches or CM.

Explanation An invalid value was specified on the second line
of the Form Length field on the Print Attributes Detail panel. This
field identifies the page length that can be printed without reconfiguring
the printer; the second line indicates the unit of measurement (inches
or centimeters) for the page length.  

User response On the second line of the Form Length field, type
either Inches (with an uppercase "I") or CM.  