Value cannot be null. Parameter name: x

Don't get confused, when trying to find where this error message was thrown: "Value cannot be null. Parameter name: x". Especially, when this is something thrown during AIF processing.

You might suggest that this is a label and you do find the label @SYS91439, but still you have no idea what is going on, e.g. no breakpoints with this label are hit.

So, it may well be something thrown by an arithmetic operation, which was passed a null value.

Another good reason to give meaningful names to variables and check for null values.

AIF: Mind auto-generated Axd<DocumentName>.findCorrespondingAxBC method

Problem

You have just created a document service with the wizard. You need the document to contain an unbound value. So, you create a display method on one of the tables, and add a corresponding parm-method to Ax<TableName> class. Then you refresh the services, but the new field is not presented in the schema.

Solution

Check the new Axd<DocumentName> class. By default, it may have findCorrespondingAxBC method, overriding the base class method and always returning classnum(AxCommon). This is why your new parm-method in the Ax<TableName> class is ignored.

P. S. There are actually TODOs added to the auto-generated methods. It may be a good idea to clean up the TODOs first, and then continue with the service development.