The domain or server is only optional if the GUID you want to bind to is in the same domain as your client. I have found that when binding to a GUID from another domain (in the same forest) some value is needed or the binding fails.
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This seems to be the case when using an NT4 account binding to the AD. When logged on with an AD account this does appear to be truly optional.
Edited by Howard Bullock (2004-01-16 07:30 PM)
