Failed to send a document to BizTalk-Server

Hallo, when I try to send a document to BizTalk Server with the function Send() in codeunit 99008517 “XML Document-Create” so this function returns me the value 100, wath will indicate a failure of the Send() method from the automation object ‘Commerce Gateway BTS Access Client’.Document and the document to send is not transmitted to BizTalk Server. There are also no messages in the Eventlog on the client and on the server computer. Navision Attain 3.60 will return with the message “An unknown error has occurred”, but waths the reason for this error? Thanks in advance for any response.