I don’t believe that there is an XPI adapter for webMethods 6. You said you installed the Enterprise XPI adapter, which implies that it was developed for webMethods Enterprise 5 (or earlier). You need to have the earlier webMethods tools to configure the adapter - specifically, you need Adapter Manager to set up the adapter and Enterprise Integration to write code. An Enterprise Adapter needs to connect to a Broker, so make sure you have your webMethods 6 Broker configured and running. You’ll be able to write code that publishes and receives Broker documents, which can in turn be used to communicate with webMethods 6 IS code.
#webMethods#Integration-Server-and-ESB#Adapters-and-E-Standards