Most small check scanners do not have the ability to set the endorsement (inkjet) text for the item that is currently being scanned. Therefore the SetEndorseText() call is not supported in this case. This is a limitation of the check scanner.
You can determine whether SetFixedEndorseText should be called by examining the following value:
UsesFixedEndorsement = Ranger.GetTransportInfo("General", "UsesFixedEndorsement");
If UsesFixedEndorsement = "True, then your application should call SetFixedEndorseText() before feeding the first item and again during each NewItem event.
Please refer to Ranger API documentation's description of SetFixedEndorseText(), for more information regarding this method and the valid Ranger states from which it can be called.