Last week, I spent some time looking at a problem with a customer’s orchestration. In one place, the developer had made use of the infamous BizTalk xpath() function to assign a value in one messageto a decimal field in another message. He got an error stating that the application is “Unable to cast object of type ‘System.Double’ to type ‘System.Xml.XmlNodeList'”. This is due to a logical error in BizTalk’s code. Read more at