You cannot run an action in the XML Transformer for an XPath that has a reference to a default namespace(xmlns not followed by : something). This is a standard issue if you need to XML transform the UBL XML format.
Here is an example of a default namespace:
In this example we would like to create a delete action for the cbc:CopyIndicator document that contains a default namespace ( xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2 ) on the root node Invoice.
Since you cannot use an XPath in the XML Transformer Form to select the Invoice node directly, you must enter the Namespaces dialog:
1. Click XML in the Toolbar. select Namespaces to assign a prefix for the default namespace.
2. In this example we can assign a prefix for urn:oasis:names:specification:ubl:schema:xsd:Invoice-2 with the name def.
3. After assigning a prefix for the default namespace you can add the delete action using the newly created prefix for the Invoice node.