Convert HTML to pptx, odt, docx, mhtml, or jpg formats throw exception using following code example. You can use any input html file.
Sample Java code example to reproduce the issue.
Converter converter = new Converter("input.html");
// Get conversion option for final output document
ConvertOptions op= converter.getPossibleConversions("docx")
.getSource().getConvertOptions();
// Save the DOCX to disk
converter.convert("out.docx", op);