The process or template contains a form field (in either a task form or a launch form) whose field type is select, checkbox-group, radio-group or autocomplete.
The value submitted for this field must be an array of strings. The strings must be option values, NOT labels..
The values specified in the array must be selections specified in the field's options list unless the the field configuration permits unlisted values.
If the field is a Select field with multiple = false, or if the field is a Radio or AutoComplete field, then the field must contain AT MOST ONE value.
Possible Causes and Suggested Actions
The value of one of these 4 types of selection fields is incorrect.
The value needs to be replaced with a valid value.