Error Message "Key Sequence columns are not supported at the case level"

Hi group,
I was trying to build a sequence clustering model in MSAS.
I could deploy the model. Then while building the model, I end up getting an error with message "Key Sequence columns are not supported at the case level".

Can some one tell me what it means and how i can avoid it?

Thanks in advance to any kind of help here.
The Microsoft_Sequence_Clustering algorithm requires the sequence
information to be modeled as a nested table so you can only have a nested table column with Content=Key Sequence (right-click on the column in the Mining Structure tab and look at the Properties pane).

In the above case, you will have a case level key that uniquely identifies a sequence set (modelled as multiple nested table rows) and you'll need to mark that with Content=Key and IsKey=True.|||Thanks for your suggestion Raman.
I have made the change that you have suggested and proceeded to the processing step.

Hmm, the processing fails with error msg:
"OLE DB or ODBC error: A column has been specified more than once in the order by list. Columns in the order by list must be unique.; 42000."

The "Key sequence" column in the nested table has been used twice in a query. Query attached in the end for reference.
What could be the cause for this? / How do i make AnSer stop generating this wrong query?
(How do you like my new short name to MSAS? AnSer. Sounds like 'answer') :)

FYI.. the "Key Sequence" column in the nested table has a FK relationship with the "Key" column of the case table.

The processing fails because it runs the query:
SELECT
[nestedTable].[col1]
,[nestedTable].[col2]
,[nestedTable].[col3]
FROM [nestedTable]
ORDER BY [nestedTable].[col1]
,[nestedTable].[col1]
--col1 is a sequence key and has FK relation with the case table.|||The "Key Sequence" is the key of the nested table, while the foreign key
should be the column you used to join case table
and nested table. These 2 columns should be 2 seperate columns in the nested
table. The following is an example:

SeqClustCase -- Case table
UserId (Key)
A1
A2

SeqClustNested -- Nested table
UserId (foreign key)
Order(Key sequence)
Sequence (sequence data)

Please try fix your data source view and mining structure according to the
above example.

Thanks,|||

Actually the foreign key column is implicitly included as part of the bindings for the nested table when you use BI Dev Studio and you don't need to specify it as a column in the nested table.

Can you please post your mining structure and model definitions?