In SSIS when we will create task where data source is XML source.
We may get a warning message like:
For security reasons DTD is prohibited in this XML document. To enable DTD processing set the ProhibitDtd property on XmlReaderSettings to false and pass the settings into XmlReader.Create method.
Cause: Your XML file also contains DTD (Document Type Definition).
Solution: SSIS doesn't support DTD in XML file. So remove the all DTD from your XML file.