Error: "User cancelled this action."

I'm trying to import and XML but I always get "User cancelled this action."

var doc = app.open(File('/c/files/test.indd'));

var xml = File('/c/files/test.xml');

doc.importXML(xml); // <-- It halts execution on this line with: User cancelled this action.

doc.exportFile(ExportFormat.PDF_TYPE, File('/c/files/test.pdf'));

Any help or some direction to a decent manual would be highly appreciated.

Regards