When you create an XML schema in 5.3 SP1 based on the same XML file, the resulting XML Schema is very different. Namespace prefixes are suddenly missing, causing the message to become invalid. Because of this, it’s impossible to add an additional field to the existing mappings without completely redoing the mapping.
Previously in Adeptia Suite V 5.2 we were creating DTD of the XML file in the back-end but now in Adeptia Suite V 5.3 we are creating the XSD of the XML schema in back-end. When the XML contains namespaces, then it is always advised to un-check the "Convert to XSD/DTD" option while creating XML schema using XML file.
Please follow below steps for resolving this now:
1. Modify the XML schema.
2. Create XML schema but make sure that the "Convert to XSD/DTD" option is unchecked.
3. The elements added will be automatically populated in the Data mapper.