Attribute key cannot be found. Value 0 . eventhough set to unknown member

Question

Hi,
I want to be able to set any null values in the fact foregin key to the dimensions unknown member.
I have a dimension called agent , with UnknownMember = True and UnknowMemberName = No Agent. When I process my dimension, I see all my agents plus a No Agent member. (ErrorConfiguration = Default. I do not want to ignore errors ).
In the cube dimension usage I've set null proccessing to unknown member.
I have a rows on my fact table with NULL on the agentID and the Cube fails to process with this error (its changing NULL to 0):
Errors in the OLAP storage engine: The attribute key cannot be found when processing: Table: 'dbo_FactSales', Column: 'AgentId', Value: 0.
I was expecting that, based on my configuration of the dimension, that the NULL row would be assigned to the unknown member of the dimension.
What am I missing?
(I know that I could have a Unknow record on my db and deal with it on the ETL process, but I would like SSAS to handle this situation. I already read 
http://msdn.microsoft.com/en-us/library/ms345138.aspx is telling to do on the section "Referential
Integrity Issues in Fact Table")
I don't know if this is related but the fact value is taken from DSV query of:
CASE WHEN Fact_table.[AgentId] IS NULL THEN NULL ELSE CAST(Fact_table.[AgentId] AS INT) END AS [AgentId]
Your help appreciated
Namnami

Answer 1

Hi Namnami,
Please refer to the following article:
Defining the Unknown Member and Null Processing Properties:
http://technet.microsoft.com/en-us/library/ms170707(v=sql.90).aspx
Here is a related article about this error message for your reference:
SSAS Quick Reference: Attribute Key Cannot Be Found:
http://toddmcdermid.blogspot.com/2009/01/ssas-quick-reference-attribute-key.html#!/2009/01/ssas-quick-reference-attribute-key.html
Regards,
Elvis Long
TechNet Community Support
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