I found out what you probably what you insignuated; that you cannot specify "null" when creating a creditor as you can with a debitor. I have now altered the service, so the same is possible with creditors. It will, though, take a few weeks, before it is released. Till then, you can do something like this:
```
public static void CreateDebtorWithAutoIncrement()
{
using (var session = new EconomicWebServiceSoapClient())
{
Connect(session);
var nextCreditorId = session.Creditor_GetAll().Select(p => int.Parse(p.Number)).Max() + 1;
var creditorHandle = session.Creditor_Create(nextCreditorId.ToString(), session.CreditorGroup_GetAll().First(), "auto-incremented", VatZone.EU);
Console.WriteLine("Created creditor with id: '{0}", creditorHandle.Number);
}
}
```
/Morten