docx4j No xpathStorageItemId found - docx4j

Question

I am using docx4j to bind a custom XML part to a word document, but I get an error message that I cannot resolve. I have done these steps:
Inserted content controls into a Word document.
Create an XML file with data.
Use the Word 2007 Content Control Toolkit to bind the cuxtom XML parts to the content controls.
When I open the document the binding is successful and the XML data appear in the document. However, when I run Java code to bind the docx file to the xml file I get an error:
org.docx4j.openpackaging.exceptions.Docx4JException: No xpathStorageItemId found, does the document contain content controls that are bound?
The code I am using to make the binding is from the docx4j examples
try{
WordprocessingMLPackage wordMLPackage = Docx4J.load(new File(input_DOCX));
File inputFile = new File(input_XML);
FileInputStream xmlStream = new FileInputStream(inputFile);
Docx4J.bind(wordMLPackage, xmlStream, Docx4J.FLAG_BIND_INSERT_XML & Docx4J.FLAG_BIND_BIND_XML);
Docx4J.save(wordMLPackage, new File(OUTPUT_DOCX), Docx4J.FLAG_NONE);
System.out.println("Saved: " + OUTPUT_DOCX);
}catch(IOException ex){
ex.printStackTrace();
}catch(Docx4JException ex){
ex.printStackTrace();
}
There are some content controls on the document that are not associated with a custom XML part. Could that be the cause of the error? Must all content controls have an XPATH?