I tried to use the latest version of Aspose HTML yesterday and got an exception when setting the license:
Root cause: org.xml.sax.SAXParseException: The processing instruction target matching “[xX][mM][lL]” is not allowed.
at org.apache.xerces.parsers.DOMParser.parse(Unknown Source)
at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown Source)
at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:122)
at com.aspose.html.z14.m72(Unknown Source)
at com.aspose.html.z14.m1(Unknown Source)
at com.aspose.html.License.setLicense(Unknown Source)
Turns out, it tries to load the file
com/aspose/html/Aspose.License.BlackList.xml
and fails because this particular version of the file starts with a blank line before the actual start of the XML documents:
<?xml version="1.0"?>
This confuses the Xerces XML Parser (latest available version).
The blacklist file of version 20.8 did not start with a blank line.